To address some of the common situations videographers face when creating corporate or online videos, we have launched a three-part video series. The topics include: How to Mic Someone at a Computer; How To Sync Audio and Video; and How to Mic a Walk -and- Talk.

How To Mic A Walk-and-Talk

The “walk-and-talk” video featuring a company spokesperson is a popular way to help people engage with your brand.  In this video, we’ll show some ways to record professional-sounding audio in an office or industrial environment – even when the subject is moving.

To address some of the common situations videographers face when creating corporate or online videos, we have launched a three-part video series. The topics include: How to Mic Someone at a Computer; How To Sync Audio and Video; and How to Mic a Walk -and- Talk.

How To Sync Audio and Video

One way to improve the sound quality of your videos is to use an external audio recorder.  But how do you synchronize the recorded audio track with the video from the camera when editing?  In this video we demonstrate an easy method whose roots go back to the early days of talking pictures.

To address some of the common situations videographers face when creating corporate or online videos, we have launched a three-part video series.  The topics include:  How to Mic Someone at a Computer; How To Sync Audio and Video; and How to Mic a Walk -and- Talk.

How to Mic Someone at a Computer.

Miking someone sitting at a computer for a podcast or webinar seems simple, but mic choices and room noise often conspire to deliver poor sound.  In this video, you’ll be able to compare the sound of different types of microphones, and learn how to overcome the effects of a noisy room.

Contributors: Keith Anderson, Videographer and Chris Lyons, Manager of Technical & Educational Communications at Shure

Shure UR5 Wireless Diversity Receiver

For the videographer who is either earning a living or bringing in some extra income by shooting video for weddings, events or the Internet – audio can present a challenge.   You can’t have a bride holding a microphone while exchanging rings or conventioneers tripping over cables in a convention hall where a manufacturer is shooting a new product introduction video.  Enter wireless.

How it Works

Wireless systems for video have become increasingly popular in the last few years for their many freedom-of-movement advantages. Think of it this way: a wireless microphone system is really a miniature radio station. A microphone cartridge (dynamic or condenser) converts incoming sound waves to an electrical signal. The signal is sent out by a low-power transmitter, and then picked up by a receiver located nearby, which converts the radio-frequency signal back into audio. The transmitter can be contained in the handle of the microphone or in a small bodypack. A cable then connects the audio output of the receiver to the input of the camera or a separate recording device.

Portable Systems

Portable battery-powered wireless diversity receivers, like the Shure UR5, are available for use in situations like the ones above, where both the transmitter and the receiver are moving around.  A complete system (wireless mic, transmitter and receiver) can cost between $1500 and $2000, but the benefits for the pro or semi-pro far outweigh the initial sticker shock.

Portable wireless receivers are very small — usually about the size of a deck of cards (or according to Chris Lyons, two iPhones) — and can be worn on the body or mounted directly to a small mixer or camcorder. Size does matter – the receiver has to be small enough to mount on the camera without weighing it down.  A short cable connects the audio output of the portable receiver to the audio input of the mixer or camcorder.

The classic application is creating an event video. The talent (or maybe the pastor if it’s a wedding video) uses a lavalier with a bodypack and the battery-powered wireless receiver is mounted on the videographer’s camera.  Because the UR5 is a single channel receiver, additional systems are required for additional sound sources.  One speaker, one transmitter, one receiver. It’s how Shure records videos like this one.

Here’s Chris Lyons demonstrating the ULX-D Quad and Dual Receivers

Lavalier: WL150, Bodypack Transmitter: UR1, Wireless Receiver: UR5

Recording Audio

The first option is the easiest: connect the output of the receiver into the camera’s mic input.  Audio quality is dependent on the quality of the audio circuitry that’s built into the camera and for many high–end pro cameras, the audio quality can be pretty good.

The second option is using a separate recording device. Increasingly popular DSLR cameras offer superior image quality but the audio circuits aren’t typically up to professional standards.  The dynamic range isn’t great, it’s difficult to control levels and hiss can be a problem. Serious shooters generally use a separate audio recorder.

A key feature of the UR5 portable diversity receiver is that it comes with two output cables -  one with a standard XLR connector for a pro camera, recorder or mixer and a second output cable with a 3.5mm mini plug for DSLR cameras. There’s an available cable that will work for any type of camera.

It also offers a separate headphone output, so that the camera operator can monitor the audio through headphones or an earpiece – effectively minimizing or eliminating “what’s that sound?” issues in playback.  There are seldom ‘take twos’ in weddings, speeches or corporate events.

Watch the UR5 Portable Diversity Receiver Video

 UR5 and Pro Videographer Keith Anderson

We wanted to know what, beyond the powerful Shure image and the sturdy construction, real video pros liked (or didn’t) about the UR5 receiver in a field that’s dominated by two well-entrenched competitors. Luckily, we connected with veteran Nashville sound engineer-turned-videographer Keith Anderson who just a couple of years back, traded in a competitive system that he loved for Shure.

What’s a typical set-up for you?

We shoot a little bit of everything – from high-end weddings to corporate training videos.  In fact, I just did the Steadicam work for the Chicago Blackhawks scoreboard video – so I shoot all kinds of different things. There are always two of us and I handle all the audio in addition to the second camera.  I’m running four UR5s, four UR1s (bodypack transmitters) and occasionally I run two UR3s (plug-on microphone transmitters) in place of the two UR1s.  Most of the time it’s four UR5s and four UR1s.

I always use a separate recording device because for the past three years, I’ve been using DSLRs and they’re not designed to take an external audio signal. They’re just not designed for audio acquisition.

I’ve got an audio bag that allows me to record a total of six tracks at once. I use the four mic inputs to record audio on their own individual discreet tracks and in addition, the built-in stereo microphone gives me the ability to record ambient audio using either the X/Y configuration or omni.  I typically record a stereo track of X/Y ambient and the four-tracks being fed by outputs from the 4 UR5s.

What were you using before Shure?

I was using a Lectrosonics 201 system – at the time, it was the only pro solution in audio for film or video.

I’d been through several other wireless solutions before that – an AKG system that was about $600 before I moved up to the Sennheiser system at around $800 and then I finally ended up spending about $3500 on my Lectrosonics system. 

I have since sold my Lectrosonics unit.  The Shure UR5 gave me that much confidence. 

Where’s all this love coming from?

It comes from the confidence of having a device like the Shure UR5 that allows me to visually see the air that’s clean.  No wireless frequency issues.

With other devices, I’d keep my fingers crossed. They didn’t offer any graphical representation of the clean frequencies. With the Shure UR5, I’m able to find the clean air really quickly using a feature called Spectrum Scan.

The first thing I do when I get to a venue is run Spectrum Scan and it gives me an instant graphical image of how much clean air is around me. Once I land on a clean frequency, I’m so comfortable with the reliability of the system that I don’t continually monitor the audio anymore. 

I run four devices at once and I’ve never had a single problem. Once I run a Spectrum Scan or Group Scan, everything’s been perfect, rock-solid – I’ve never had a dropout once.

Two cameras and lots of systems.  How do you sync the audio?

I use a software call PluralEyes®.  I go into my NLE (non-linear editor) of choice  – I’m an Adobe Premier CS6 guy – and take all the video and lay it on the timeline, take all of the audio tracks (and in my case, they’re already synced in the multi-track recording) and lay those on the timeline. Then I just open PluralEyes and hit the SYNC button. I walk away and depending on the length of the timeline, come back in a little while and it’s all synced up.   Enormous timesaver.

Here’s an event video Keith shot using the Shure UR5 portable diversity receiver and with a UR1 bodypack transmitter and UR3 microphone transmitter.

Any unusual applications?

We shot a project where we were spoofing a few movies and I had the UR1 on an actor who was rolling down a hill – he rolled over a few times on the UR1 and not only did it sound great, it came out unscratched.  I was really grateful for that.

What about a few basic UR5 tips for our readers?

1. Use Spectrum Scan to handle frequency issues.
2. Use the same UR5 and UR1 combination in the same type of situation every gig.

Example: Each of my UR1s is set up with a slightly different gain structure. I have a UR1/UR5 combo with the gain setup for a person who speaks loudly or projects and another UR1/UR5 setup for a person who speaks in a quiet tone. When shooting a wedding, I’ll use the UR5/UR1 with the gain set accordingly on the person who speaks loudly. Almost 100% of the time it’s the clergy because the clergy knows how to project. My other UR5/UR1 combo is reserved for the groom. This is designed to capture the softly spoken vows by both the bride and groom so the gain is set a little higher for someone who will probably be speaking softly.

Anything else?

This system is so much better than anything on the market. It’s so much smaller and it offers everything that competitors offer – and more. The battery consumption is much much better and it’s easier to use. 

 Shure UR5 fan Keith Anderson

Editors’ Note: The ubiquitous Chris Lyons is pretty often our go-to guy for technical posts.  He’s the Manager of Technical & Educational Communications at Shure and appears in many of Shure’s videos and podcasts. In 2002, Keith Anderson, after many years in Nashville working as a recording engineer for a prominent producer, found his passion in film and video.  He works on a wide variety of projects, but you can see his amazing wedding videos (and they are worthy of DeMille or Coppola) at www.weddingdaycinema.com

But if you spend any time on YouTube, Hulu and other UGC sites, you’ll notice that the audio (especially when a subject is speaking) can be garbled, muddy and unintelligible.  If there’s one thing we’ve learned, it’s that audio quality can make or break any video project. No matter how creative and professional the visual aspects of a production may be, these qualities can be completely negated by lackluster audio. According to one videographer we know, “It’s easy to fool the eye, but it’s a lot harder to fool the ear”.

Creating good audio can be a real challenge when shooting video – especially if you’re using a consumer-grade camcorder. Mics that are built into camcorders aren’t really designed for high-quality audio.  They are designed for sound sources that are very close to the camera and they tend to pick up a lot of background noise.

We like how video expert Israel Hyman puts it: “The microphone is in the wrong place. Frankly, the reason the microphone is on the camera is because it’s built for the camera operator to do the talking. If you’re a parent narrating your child’s birthday party, this is perfectly fine. It will get your voice and your child’s voice (even though it will sound distant). If you’re aiming for a more professional sounding video, you don’t want the off-camera, out-of-frame camera operator’s voice. You want the microphone on the subject”.

Adding an external mic – a handheld, lapel (or lavalier) or a shotgun mic – gives you what matters the most – the best signal-to-noise ratio.  In this Shure Notes® blog post, we’re going to give you some tips about the third type – the shotgun mic. Its extremely directional pickup pattern (called a line/gradient pattern) makes the shotgun mic popular for TV news and movie sets.

The shotgun microphone is named for the long, slotted tube in front of the microphone cartridge that makes it resemble a shotgun. This “interference tube” helps reject sounds coming from more than about 30 degrees off to the sides, while still picking up sounds from the front.  Because a shotgun mic is either mounted to a camera or a boom, it is rarely seen by the viewer.   In fact, it’s almost impossible to imagine a situation in which the mic should appear in frame (unless you’re making a video about making a video).

Advantages

Let’s talk about what shotguns mics are not: They are not telephoto lenses for sound. They do not allow you to zoom in on a conversation from 100 feet away.

Here is how Shure’s Chris Lyons explains it: “Imagine looking through a long tube at a person standing 20 feet away. The person’s image does not appear to be any larger or closer, but is somewhat easier to see, because the eye is not distracted by things happening off to either side.”

This is exactly what shotgun mics do best: they screen out sounds coming from the sides. In practice, a shotgun microphone can typically be placed at four to five times the acceptable distance for a standard omnidirectional microphone. But keep in mind that the shotgun mic will also pick up sounds coming from behind the subject.

Tips for Using Shotgun Mics

• Shotgun mics can be positioned slightly above, below, or to the side of the sound source, so that the mic doesn’t appear in the camera frame.
• Try to avoid aiming the mic at a hard surface, such as a tile floor, brick wall, or hard ceiling. These surfaces reflect sound waves, and may reflect background noise into the microphone or cause the sound to be slightly hollow. (A heavy blanket can be placed on a reflective surface to provide some temporary sound absorption.)
• Shotgun mics are more sensitive to wind noise than standard microphones, so try to avoid moving the mic rapidly and use a foam windscreen if possible.  (Larger “zeppelin” or “blimp” type windscreens are usually necessary outdoors.)
• It’s a good idea to use a rubber-isolated shock mount to control handling noise that may be transmitted through a stand or boom.
• If you’re using a boom for a scripted video, make sure your boom person has a script.  If more than one speaker is going to be miked, the boom person needs to point the shotgun at the right person at the right time, a challenge when the mic needs to remain out of frame, the sound has to be consistent and the boom may be over 20 feet long.

What to look for when buying a shotgun mic

Mics with a balanced XLR outputs signals will give you better noise and interference immunity.   Remember, too, that if you have a stereo mini-jack input on your camcorder, you’ll need to get an XLR camcorder adapter that will allow you to use professional quality microphones.

Shure offers two end-address shotgun condenser microphones.

VP89

Offers a choice or interchangeable long, medium and short capsules.  Hand-tuned and assembled in the US, offers natural off-axis rejection without coloration.

VP82

This mic is designed for camera-mounted applications.  It is extremely lightweight and has an integrated preamp.

Want more information?

 Check out the Shure educational video on Shotgun mics shown above!

Interview with Mark Jensen.

You’re an IT guy and a voice-over talent, in addition to being the force behind NewMediaGear.com and Studio1A Productions. Can you explain how these inter-relate?

I am fascinated with technology. This drive rages stronger now than ever before. From on-air radio guy to Senior Global IT Engineer and finally media entrepreneur, being at the forefront of technology has relentlessly guided my careers.

Analog, digital (HD), satellite and even streaming radio all have common bonds. Computer technology slowly, then rather quickly, swept its way into audio. Information Technology is embedded in almost every facet of our lives, technically and artistically – from electronic books, smartphones to broadcast and recording – technology rules.

In this issue, we’re talking about audio for online video, thinking specifically, about creating better web/YouTube videos than the kind that might be created using a mobile phone, webcam or camcorder’s built-in microphone. So, let’s start with – what’s wrong with using one of those built-in mics?

In the short term, these low-quality, integrated microphones seem fine. But, when we think long term, cutting corners with technology deals us a terrible blow. Think about being able to go back in time and actually hear the voices of people and experiences that can never be re-created– decades or even centuries old. Wouldn’t we want to capture those moments with as much sonic clarity as technology allows? True, it’s not practical to carry around a sound studio.

However, with kits like the Shure SM57/X2u and the USB port on your laptop, it’s becoming much more practical to capture professional audio on the go.

There are as many mic options, probably, as there are broad categories of online videos. What mic recommendations and tips do you have for specific applications?

First, remember that the most expensive microphone is rarely the best choice. In a world of picky sound engineers and thousands of choices, few would disagree that the affordable SM58® is the most popular, versatile microphone in the world.

Let’s say we want to capture the voice of a strong vocalist, singing lead. Right away, I think of condenser microphones. Most large diaphragm condenser mics are very sensitive, able to capture subtle nuances and wide dynamics. With that heightened audio acuity, and without a sound studio, you run the risk of recording your neighbor’s dog barking or the subtle sound of a door closing on the other side of the house.

How about recording narration for a video? Here, a good dynamic microphone works great because it’s a passive device and won’t generally be as sensitive to ambient sounds. Yet, a good dynamic microphone will brilliantly capture the mood of speech.

Social journalism intrigues me. Here, a reporter style, tough as nails (an SM57 with wind screen comes to mind) dynamic works great. They may have better lighting and cameras, but with some experience, an individual can match the audio quality of your local television station.

I grew up around radio broadcast microphones. If you have a dedicated room, and want that radio look to your video, try an SM7B on a boom. If you want a retro look, blow them away with the timeless Super 55.

If you’re recording several people, using a single microphone, I would huddle them around an SM58. This mic is known for being able to take on a completely different character by close or medium talking the mic. Have you ever watched a comedian on stage wrap their hands around the microphone head, achieving a bassy, or even muffled sound for dramatic effect? This is proximity effect and the SM58 made this stage technique famous.

What are the most common mistakes beginners make producing their first short videos?

Always watch the audio levels. When it’s live, and there is only one take, set your audio record levels low on the camera. Audio levels can be boosted later, but over-driven, distorted audio can make a great shoot unusable.

If levels vary wildly, check your video camera for an audio compressor or limiter. If you’re confident the levels won’t distort (record at or above 100% or 0db), then run without the compressor. Record a few dry runs to get an idea of just how much room there is from silence to the loudest sound or voice you are recording with your camera in the scene/environment.

Don’t use video camera (or webcam) built-in audio. Take the time to assess your project. Storyboard it and plan the flow, even if you scribble something at the last minute. Effective video requires planning and coordination.

A visible microphone in your video can actually lend credibility. Microphones are frequently used on television talk shows as props. If you can dedicate room to a studio and large table, go for the classic Shure SM7B on a boom. Save finicky lavaliers for shots when a visible microphone just won’t work.

As mentioned above, don’t rely on your video camera microphones. If you are constantly on the move with your camera, consider mounting a shotgun type microphone on it. This will give you maximum clarity right where you want it.

What limitations does the Internet (or YouTube-type platforms) have on audio production?

I am blown away with the inexpensive tools and the creativity found in today’s “Tube” type videos. Professional audio/video hardware and software has never been more affordable.

While the file size, and stream time, of Internet video has made incredible progress, there are still limitations. Too many times, I see Internet video shot in 1080p and high bit depths, just because it can be done. In reality, most Internet video will be transcoded (converted) to a much lower quality that still looks incredible. For me, 720p, at a reasonable bit depth is the sweet spot.

There are other video issues beyond the scope of this article, such as rolling shutters and resolution vs. bit depth and optics. Experiment and try to get the best quality shots without maxing your cameras video settings.

In audio, bigger and pricier will not always give you better results. Some of my most inexpensive microphones get the most use. The important part is that they are all professional. To me, a professional microphone means it has a balanced (XLR connector instead of the small consumer 3.5mm unbalanced). With a product like the Shure X2u, you can instantly plug in a pro microphone while the other end goes to your computers USB connector. That type of flexibility simply wasn’t available 10 years ago.

You’re also a podcast producer. What are the similarities (or the differences) between recording for podcasts and recording for video?

I like to punch the final audio levels a little harder when creating audio-only. Ideally, I would compress my audio more because people may be listening in noisy areas or in the car with the windows down.

Video can be a little more gentle and refined because the visual helps articulate your message. Also, your viewers are typically consuming your media in a quieter environment.

Try this experiment. Listen to a few minutes of random television shows. Listen only to the audio. Then, turn on a few random radio stations. Notice the difference in overall sound? Much of that difference is due to video stage production and the stations final processor. Sometimes television sound is captured live, but high budget film and television use a technique called automated dialogue replacement (or ADR). After a video shoot, the actors will lip sync their lines in a sound studio, achieving the highest quality audio experience and advanced mixdowns. I’m getting off track here, but the underlying concepts and foundations of audio are universal.

Don’t let all of this impede your message. In the end, that famous saying is still paramount: content is king. Use the best tools available, but never lose sight of your message and your audience.

Got a favorite Shure mic? What do you like about it?

I do! It’s a PG27. There is just something about the way that microphone articulates my voice. It’s ultra crisp and clean. It always gets the job done. Being a studio condenser, it is larger than most hand held microphones, but the sound is amazing for speech.

ABOUT MARK JENSEN

Mark lives and works in Orlando, Florida with his awesome wife Laura. He is a Microsoft Certified Systems Engineer, FCC licensed radio operator, national media producer and agency voiceover talent, while running his flagship syndication NewMediaGear.com.

You can reach Mark at: mark@newmediagear.com

Let’s say you’re not quite ready to invest in a professional rig and you’re planning to get started by using a basic consumer model. While you may have to make trade-offs in optical features like zoom choices and video standard (is HDE important?), we asked expert Mark Shapiro, editor in chief at Internet Video Magazine, to lend a clear, intelligible voice.

Creating good audio is the most difficult challenge when creating Internet videos – especially if you’re using consumer-type camcorders. It’s easy to fool the eye, but it’s a lot harder to fool the ear.

If you make a mistake with audio, the ear will catch it while the eye is a lot more forgiving of video problems and inconsistencies. And if you spend a lot of time on YouTube and other user-generated video sites, you’ll notice that the sound on many of the videos is garbled, muddy and often unintelligible.

Take heart. There are many ways you can make your videos sound a lot better without having to spend lots of money, go to film school or hire a sound engineer to help you shoot your video short. Here are seven.

1. Use an External Microphone

If possible, use an external mic. Unfortunately, the microphones built into most camcorders are not very good. Even worse, they’re omni-directional and will pick up sound from everywhere.

Even though most of these mics have a somewhat ellipsoidal pickup pattern (aimed more toward what is in front), most camcorder mics will pick up mumbling, heavy breathing and other extraneous noises. A few camcorder mics will allow you to slightly focus their mics from wide angle to narrow.

And here’s another issue: on many camcorders, the mic is not well located and can easily get in the way of fingers adjusting focus, activating effects and zooming in.

The good news is that digital camcorders record digital sound. This means you should be able to record high fidelity, stereo, and CD-quality sound assuming you can get the audio into the camcorder in the first place. This is why you need an external mic that plugs into the MIC IN jack on your camcorder. Most good camcorders will have a MIC IN connector as well as a shoe to mount the mic on.

Unfortunately, many of the more affordable camcorders – especially those tiny “pocket size” camcorders, do not offer an external mike  connection at all and you need to rely on other tricks to improve the audio.

Many camcorders also offer active “hot shoes”. This allows you to plug an external mic onto the “shoe” and transmit the audio directly from the mic to the camcorder’s electronics.

If you’re on a limited budget, the best choice for an external mic is a basic telephoto or shotgun that can be adjusted to zoom out when you want to capture the sound from a crowd or zoomed in when you want to capture sound from a source a good distance away. And if you can afford to upgrade, go wireless and get a wireless lavaliere system. Even better, get a wireless kit with a receiver that mounts on the camcorder and includes both handheld and lav wireless mics.

2. Use Lavalier Microphones

A wireless microphone system is usually a bit more expensive than a basic shotgun mic, but allows you to get much better sound.

I prefer using these for shooting interviews. Instead of using a handheld mic or a shotgun mic, simply pin the wireless lavalier and its transmitter to the interviewee’s lapel or jacket and then the sound of their voice will be transmitted back to the receiver unit that is mounted on your camcorder.

In most interview situations, you don’t really need to hear the questions except for in the editing process. Of course, if the interviewer’s voice is important, then use another lav mic or have them hold a mike. Feed both mics through an audio mixer and then into the camcorder.

FYI – In many video interview situations, one camera is used to capture video and sound of the interviewer and a second camera is used to capture video and sound of the person being interviewed.

3. Close Mic

If you don’t have a shotgun mic or good wireless microphone system, or if your camcorder doesn’t have an audio input jack, then the next best thing is to get close.

If you need a long shot for artistic reasons, you might want to shoot the scene again – just for audio. Have your actors do their lines a second time so that you can get good quality audio and then dub it in later to replace the bad audio. If the shot is far enough away, the audience will never notice that the actors’ mouth movements don’t exactly match the audio.

During the editing process, you can also have your actors re-record the audio, duplicating the original dialog so that it matches. You might want to use the same camcorder to record the audio so that the audio quality matches. Also, this is where room tone can be very important.

Most camcorders have an electronic circuits built into them called AGC or Automatic Gain Control. It automatically adjusts the sound recording level so that the camcorder will pick up something, no matter how faint. The further you are away from your sound source, the more the AGC has to magnify the sound. The more it amplifies the audio, the more it also amplifies the surrounding noise as well.

If the audio source is faint, the camcorder may adjust the AGC pick-up sensitivity so high that it even picks up the sound of the camcorders motors and gears.

And don’t forget – getting close will not only make your audio sound better, it will make your video look better.

4. Record Continuous Sound of Events or Performances

If there are problems or breaks in the audio, it’s almost impossible to cover them up by using creative editing. If a visual doesn’t quite match or you get a strange out of focus shot or two, it’s easy to replace it with a cut-away or new angle. But with audio, your audience will notice every small change and gap in the recording.

When you record a performance or event, make sure you record and capture the sound as a continuous event – without any breaks. While the camcorder is rolling and capturing the sound, you can be zooming in and out, getting different shots, shooting close-ups, and so on.

For example, when I was in Hawaii with my kids, I taped my kids’ hula lesson. Later on, it was easy to edit the video by just inserting shots of new video over the clean audio track. In addition the shots of the class itself, I inserted visuals of the entire Hawaii trip.

5. Monitor Your Audio

If your camcorder has an earphone or headphone jack, use it! Especially when recording tricky audio situations like concerts and live performances. Even though you don’t want to be recording where the audio levels are too low, you also don’t want audio that is too loud or distorted. In concerts, it may be helpful to turn the mic away from the stage and catch the sound coming from the ceiling.

By using headphones, you can monitor the sound. This is very important when a dead battery or a disconnected mic plug or cable may spell disaster.

6. Use a Portable Audio Mixer

Professional video makers just don’t plug their mics directly into the camcorder and record raw sound, especially when recording a concert performance.

By using a mic mixer with level controllers, you can use several mics to get the best quality sound for recording stereo. Most mic mixers also provide a headphone jack for monitoring the audio quality as well as record volume dials. On many pro camcorders, this mixer and volume control system is built into the camera. And some camcorders allow the operator to record, control and monitor up to four different audio tracks.

7. Capture Room Tone

If you plan on editing your videos, you’ll want to remember to capture a minute or two of room tone (or the ambient sound of the location when nothing is happening).

Every location has its own background buzz. It can be the sound of the surf pounding away in the distance, it can be the sound of the city outside the walls of a ballroom, and it can even be the soft buzzing of the lights and electronics in an office. By recording this background tone and using it while editing, you will be able to insert it into your video to cover any gaps in your audio recording. By cross fading from the good sound to the background tone, the loss of audio won’t be as jarring as going from voices and singing to deafening silence. If you are mixing in new sound or recording dialog, you can help make it seem like it really belongs by mixing it with the environmental sounds.

If you are able to integrate these seven tips above into your daily video shooting process, you will find that your videos suddenly seem to be much better. Your friends and family might not be able to put their finger on it they may not be able to isolate what has improved, but they will definitely better appreciate your work.

Mark Shapiro, has been producing and writing about video for over 35 years. Internet Video Magazine, launched in 1999, is the web’s best source for how to shoot, edit and post Internet videos destined for business and personal sites, as well as for public sites like YouTube and Vimeo.

Tim Vear from Shure’s Applications Engineering department can talk wireless with the best of them. In this installment, Tim shares his knowledge of wireless technology and television airwaves…past, present and future.

Why Sound Quality is Important
Popular media such as compact discs, movies, and music videos have helped to raise our standards for what qualifies as “good sound.” Unfortunately, the sound quality in distance learning classrooms often leaves much to be desired. Poor sound quality will make it more difficult for students to understand the material being presented. It may also reduce their level of interest and participation in the class. Classroom audio systems that are poorly designed or implemented will inhibit interaction between students at different class sites, because they will not always be willing to make the effort required to overcome technology barriers which prevent them from being heard.

Complaints from instructors and students about classroom sound typically run along these lines:

• “It sounds like the person speaking is at the bottom of a barrel.”
• “When someone talks, the first couple of words get cut off.”
• “We can’t turn it up loud enough to hear without getting feedback or howling.”
• “When we talk, we hear an echo of our own words.”

The technical and operational causes of these problems are rarely apparent to someone who does not have specific audio training. Fortunately, an understanding of just a few basic audio concepts can help the designer, installer, or user of a distance learning audio system to achieve very good sound quality in the classroom environment.

What it Takes to Make a Distance Learning Classroom Work
There are four main parts which make up a distance learning classroom:

• the classroom itself,
• an audio system,
• a video system, and
• a link to a transmission network.

This paper will focus on those variables in the classroom and the audio system which determine the quality and intelligibility (the ability to understand what is being said) of the sound that is transmitted to listeners at other classroom sites, and what must be done to control those variables.

While the choice of transmission medium – fiber optics, satellite, microwave, etc. – can have a significant impact on sound quality, a comprehensive discussion of the many different transmission schemes available and their strengths and weaknesses is beyond the scope of this paper. We will discuss, however, particular audio equipment which may be required to compensate for the effects on sound quality of certain transmission media.

PART 2 – THE CLASSROOM

Room Acoustics vs. the Audio System
The sound that is sent out of the classroom to other sites begins with the classroom itself. The acoustics of the room – that is, the way in which the room affects sound waves – are determined by physical characteristics, such as the size of the room and what materials are used to construct and cover surfaces such as walls and floors. If the acoustics of the room are poor, the sound picked up by the audio system and transmitted to other sites will be unclear and fatiguing to listen to. In extreme cases, voices may be nearly unintelligible, or interaction may be so difficult that teaching cannot take place.

The classroom and the audio system both have a major impact on sound quality. For sound that is crystal-clear, and for the audio system to be as cosmetically appealing and “user-friendly” as possible, both the acoustics of the classroom and the design of the audio system must be optimized. In many instances, however, certain restrictions may force compromises in one area, which must be offset by optimization in the other area. For instance, if circumstances dictate the use of a classroom with poor acoustics, then there will be little room for compromise in the design of the audio system. Similarly, if budgetary constraints or user preferences force compromises in the design of the audio system, it becomes critical that the acoustics of the classroom be very good. When a poor audio system is combined with poor room acoustics, results are usually so unsatisfactory that instructors and students prefer not to use the system at all.

Room acoustics vs. audio system: if one must be compromised, the other must be optimized in order to maintain acceptable sound quality.

When you are present in the same room as a person talking, your brain makes use of both the aural information supplied by your ears and the visual information supplied by your eyes. This combination of sight, sound, and brain power allows you to “ignore” or “filter out” some of the noise and undesired sound, and to concentrate on the desired sound (the talker.) A microphone does not have this ability, so it must be able to “hear better” than a human listener would in order to pick up clear and intelligible speech. But what makes one room sound good, and another sound poor? And is it possible to know in advance whether a particular room is a good choice – from an acoustic standpoint – for distance learning?

How to Tell if a Classroom is Acoustically Suitable for Distance Learning
Room acoustics is a broad term comprised of many components. For our purposes, there are two acoustic variables which have a major impact on the sound of a classroom: decay time and background noise level.

Decay Time — Sound waves emanate from a talker in all directions. Some travel directly from the talker to the microphone, while others take a roundabout route, bouncing off of the walls, ceiling, or floor. The reflected sound reaches the microphone later than the direct sound, and blends with it to become audible as a continuation or “smearing” of the original sound. Decay time is how long it takes for this reflected sound to weaken or “decay” to the point that it can no longer be heard. The decay time of a room is determined by its size, shape, and construction. The decay time in a large marble cathedral might be as much as 5 seconds; in a classroom with concrete block walls and tile floor it might be 1 or 2 seconds; in a conference room with thick carpeting and heavy drapes it might be 1/2 second.

If a room is too reflective, speech that is picked up by a microphone in that room will usually sound as if the talker is “at the bottom of a barrel” or “at the end of a long hallway.” This is in spite of the fact that the sound may be perfectly acceptable to a live listener in the room. In general, the longer the decay time is, the worse the sound will be.

Guidelines for acceptable decay time in a distance learning classroom

Decay time is measured with special test equipment which generates a burst of “white” or “pink” noise, and then measures how long sound persists after the noise has ceased. The measurement is typically made by a professional sound system installer or acoustic consultant in the process of evaluating a classroom for distance learning use.

Background Noise Level
Simply put, “noise” is any sound that the listener does not want or need to hear. Low levels of background noise can sometimes be suppressed or “tuned out” by the brain for a few minutes, but this quickly causes listening fatigue. As the level of noise increases compared to the level of speech, intelligibility suffers and listeners begin to miss words. Typical sources of background noise that make listening more difficult in a classroom include:

• cooling fans in computers or overhead projectors
• air ducts that vibrate or rumble
• air vents that produce an audible “rush” as air moves through them
• people walking or talking in hallways outside the classroom
• equipment rooms located next to, above, or below the classroom
• fluorescent light fixtures that hum or buzz

A precise measurement of background noise in a room can be made using a device called an audio spectrum analyzer. The noise level is measured in units called decibels, abbreviated dB. Because sounds with different tonal characteristics affect the human ear differently, measurements are made at many points across the audible spectrum. The resulting data are then compared to standardized Noise Criteria or “NC” curves to determine the acceptability of the room for a given purpose. Rooms used for distance learning, teleconferencing, and similar activities should have an NC rating of 35 or less (which is very quiet.)

Another device, called a sound level meter or SPL meter, provides an average reading of the noise level in a room. Be aware, however, that the sound level meters sold at neighborhood electronics stores are usually not capable of detecting low frequency noise (such as the rumbling of an air duct) and therefore may not provide an accurate and useful measurement of the noise level in a classroom.

How Room Acoustics Can Be Improved
In most classrooms, some improvement to the acoustics of the room will need to be made. The most common need is for a reduction in the decay time of the room, which is usually accomplished by covering some of the surfaces (walls, floor, ceiling, and windows) with commercially-available materials or panels designed to absorb, rather than reflect, sound waves.

A reduction in background noise is typically addressed by repair or replacement of light fixtures, and adjustment of or modification to air conditioning vents and ducts. Noise coming from outside the classroom is usually more difficult to control, however. Footsteps in a hallway might be silenced simply through the addition of carpeting, while reduction of noise from highway traffic or nearby equipment rooms might require major reconstruction of walls, ceilings, or floors. Reducing the transmission of noise into the room from outside sources can be very expensive, and should not be attempted without the help of an experienced acoustic consultant. In some cases, it may be wise to consider an alternate location for the classroom.

PART 3 – THE AUDIO SYSTEM

Components of the Audio System
The particular equipment that makes up a distance learning audio system varies depending on class size, seating arrangement, the subject being taught, the available budget, and other factors. Certain fundamental pieces of audio equipment are common to nearly all systems, however:

• a wireless microphone for the instructor
• desk- or table-mounted microphones for the students
• a microphone mixer to control, balance, and combine the signals from the microphones
• an amplifier and one or more loudspeakers to distribute the audio from other classroom sites throughout the room

Flow diagram of a basic distance learning audio system.

Specific information about different types of microphones and wireless microphone systems, how they work, and how to choose the best type for a particular application is included in Guide to Better Audio, a complimentary booklet available from Shure Brothers Incorporated. Specific information about amplifiers and loudspeakers is available from manufacturers and vendors of those products.

Thanks to popular spy movies such as the James Bond series and “Sneakers,” many people are under the impression that commonly available audio equipment can perform miracles, such as picking up intelligible speech from a mile away, or with a microphone hidden in an air duct. While it is probably true that a team of acoustic experts working for months with powerful computers could extract intelligible dialogue from a recording made that way, such feats are not possible during a live program or within the typical school system’s budget. Modern audio systems can perform well under a wide range of conditions, but they cannot compensate for having poor sound fed into them. Noise and reflected sound are impossible to remove once they are picked up and combined with speech.

Fortunately, there are time-tested “rules” for designing audio systems that can minimize the effects of less-than-ideal acoustic conditions. Three of these are so important that, if they are ignored, there is almost no hope of achieving satisfactory sound quality no matter how much time, money, or effort is spent.

Three Things About the Audio System that “Make or Break” Sound Quality

1. Talker-to-microphone distance

One of the most significant factors in determining the performance of an audio system is the distance from the talker to the nearest microphone. As the microphone is positioned farther away from the talker, the loudness of the speech reaching the microphone decreases, so the microphone’s sensitivity to sound – its ability to “hear” – must be increased to compensate. This causes the microphone to pick up more of the desired sound (speech), but also to pick up more of everything else – background noise, reflections, sound from the loudspeakers, etc. The farther away the microphone is from the talker, the more hollow and noisy the sound will be.

So, when it comes to microphone placement, how far is “too far”? It so happens that there is a certain distance from the microphone beyond which a talker will sound hollow and difficult to understand, regardless of what type of microphone is used or which way it is pointed. This is called the Critical Distance, abbreviated Dc. The Critical Distance is different for every room, and is determined primarily by the volume of the room (in cubic feet) and the decay time. Those talkers who are at or beyond the Critical Distance from the nearest microphone will be difficult to understand, no matter what type of equipment is added to the audio system or how it is adjusted. Given that most classrooms have a Critical Distance of from two to five feet, the following guidelines should be used for determining acceptable distance from the talker to the nearest microphone:

• less than 2 feet is ideal
• between 2 and 3 feet is good
• between 3 and 5 feet is marginal
• more than 5 feet is unacceptable

In a typical classroom, microphones should be located less than two feet from talkers.

When in doubt, always place the microphones nearer to rather than farther from talkers. Moving microphones closer to talkers is the single most significant improvement that can be made to most classroom audio systems.

The Best Places To Locate Microphones In a Classroom
We’ve discussed just how important it is to place microphones close to talkers, but where exactly should microphones be located to pick up students’ questions? The answers depend on how the classroom is used and on the seating arrangement. What subjects are taught in the classroom? If the schedule includes foreign language classes, or advanced courses that include lots of technical terms, intelligibility is critical. In this case, microphones should probably be placed on the student desks so that they are less than two feet from the talkers. Lecture-type classes that do not rely on heavy student interaction may permit slightly longer talker-to-microphone distances.

If it is likely that students will be spreading out books and papers on the desks, flat surface microphones may be inadvertently covered up, resulting in muffled sound or pickup of rustling noises. Slim, flexible “gooseneck” microphones solve this problem by elevating the sensitive part of the microphone above the surface of the desk – away from the noise and closer to the talker.

The toughest situation is when the room layout must be changed regularly. If microphones cannot be mounted on student desks or tables, the only remaining option is usually to suspend microphones from the ceiling. The longer talker-to-mic distances required for adequate head clearance when students are entering and leaving the classroom represent a significant compromise in the audio system design – one that usually cannot be completely compensated for. Excellent room acoustics are absolutely essential in classrooms which utilize suspended microphones. If room acoustics are poor or merely average, then suspended microphones should never be considered.

The Case Against Ceiling Microphones
For appearance and security reasons, it is always tempting to place microphones directly on the ceiling of the classroom, where they are out of sight and out of reach. This is absolutely the worst location for microphones, however, and virtually guarantees that sound quality will be terrible in all but the quietest and most acoustically-perfect rooms.

First of all, ceiling microphones are far beyond the Critical Distance for most rooms, making voices sound hollow and distant. Second, ceilings almost always contain air vents which produce noise, and air ducts which cause the ceiling to rumble and vibrate. Ceiling microphones are closer to these undesired sounds than they are to the students – exactly the opposite of the way things should be for intelligible voice pickup. Finally, students do not talk up toward the ceiling; if anything, they talk down at the desk or the floor!

2. Number of open microphones

An often-overlooked factor in audio system performance is the number of open microphones, abbreviated NOM. This is the number of microphones which are “live” or “open” at any moment, meaning that the sound that they pick up is being recorded on tape or heard by other sites on the network. Only those microphones which are “open” affect sound quality; mics that are turned off by a switch or turned down all the way by a volume control do not.

While you might expect that using several microphones to pick up the sound of a talker would sound better or louder than a single microphone, in reality it sounds much worse. This is because each additional microphone picks up some of the background noise and reflected sound in the room, even though it is not picking up the words of the talker.

Having four microphones turned up when only one person is speaking results in audio that is nearly 90% noise and reflected sound being transmitted to other sites.

So, if only one person is speaking and four microphones are open, the audio system is fed four times as much background noise and reflected sound as with just one open microphone, but no additional speech (because the additional three microphones are probably too far away to clearly pick up the talker.) What this means is that only the microphone nearest to the talker should be turned up. If you want to hear what a difference this can make, make a tape recording of one person talking in a room, first with several open microphones and then with only one open microphone. The improvement in sound quality that results from turning off the unneeded microphones is dramatic.

What can you do to keep unneeded microphones turned off in the classroom? There are really only three options: have a designated operator turn the microphones on and off as needed; have the students operate their own microphones; or have an automatic microphone mixer do it.

If a trained person is available to operate the sound system during every class, that person could be responsible for turning the appropriate microphones on and off when students speak. This is usually a poor choice, however, because even the best operator cannot react to a talker until a few words have already been missed – and a student’s question may only consist of a few words. Another option is to require the students to control their own microphones. This is done using Push-to-Talk or “PTT” microphones, which require the student to push and hold a button to be heard. This can be effective if the students remember to push the button when they want to talk. Depending on the age and interest level of the students, this may or may not be a reasonable expectation. Some instructors feel that forcing students to make such an effort before they can speak creates a barrier to interactivity, while others (especially those who teach several remote sites at once) appreciate the “shield” from unwanted distractions and interruptions which manually-operated microphones can provide for the instructor. An additional concern is that the students who are in the same room as the instructor usually do not feel compelled to activate their microphones when they talk, with the result that students at other sites cannot hear them.

A third solution to the problem of keeping unneeded microphones turned off is to use an automatic or “voice-activated” microphone mixer. This is a microphone mixer which automatically turns individual microphones on and off in response to the presence of sound at the microphone. Basic automatic mixers use a simple “fixed threshold” method to decide when to activate microphones. With this method, the sound level at any microphone must exceed a preset minimum (called the “threshold”) before the microphone will be turned on and the talker will be heard.

Proper adjustment of fixed threshold models is critical, because background noise levels within the classroom usually change from day to evening or even from hour to hour, and speaking levels vary significantly between individuals. For instance, if the threshold is set low enough so that a quiet talker can activate the microphone, then the system may be overly sensitive to background noise, and microphones may activate every time the air conditioning turns on, or when the hallway fills with students during a passing period. Conversely, if the threshold is set high enough to prevent such incidences of false activation, then quiet talkers may not be heard.

More sophisticated automatic mixers are available which constantly adapt to changes in background noise level. These units feature a “floating threshold” which is referenced to the level of noise in the room. Talkers need only speak slightly louder than the background noise level to activate a microphone. These systems are generally easy to set up and require almost no fine-tuning, since they adjust themselves to changing conditions in the room.

3. Microphone pickup pattern

It is beyond the scope of this document to review all of the different types of microphones available. In general, however, directional microphones should always be used in distance learning classrooms. Directional microphones (also called unidirectional) favor sounds from the direction in which the microphone is aimed, and reject sounds coming from behind the microphone. This trait offers two very important benefits which make directional microphones especially suitable for use in distance learning classrooms. First, they can be aimed toward a desired sound source (the students), and away from an undesired sound source (the loudspeakers.) This helps to prevent the sound from other sites (coming out of the loudspeakers) from being picked up by the microphones. This loudspeaker audio would otherwise be retransmitted, which could cause annoying echoes or howling. Second, most directional microphones pick up only one-third as much background sound as non-directional types, making them far less sensitive to the ambient noise and reflected sound present in the room. With less noise and reflected sound mixed in with the audio, speech is clearer and more intelligible.

Note that a directional microphone begins to lose its effectiveness as the distance from the talker increases. The further it is from the talker, the less improvement in sound quality it can offer over a non-directional model. In fact, when placed near (or beyond) the room’s Critical Distance, a directional microphone will sound just as poor as a non-directional type.

Common Problems with Distance Learning Audio Systems and What You Can Do About Them
A live, two-way interactive communications link is more complicated than a regular audio system used for public address or recording. The three major audio problems which plague distance learning classrooms are feedback, transmission echo, and reflected or “hollow” sound. While feedback and reflected sound are commonly encountered in many sound reinforcement systems, echo is unique to two-way communications.

Feedback
Feedback is the howling or squealing that is heard when sound from a loudspeaker is picked up by a microphone and reamplified. Feedback can easily occur between audio systems located in different rooms, if the microphones in each room pick up too much of the sound from the nearby loudspeakers and retransmit it to other sites, where it can be picked up by microphones and transmitted back again.

Leakage from loudspeakers into microphones, causing feedback or echo.

There are many factors which can contribute to microphone-to-loudspeaker leakage, so there are many possible solutions which may work in a given classroom. Here are the corrective measures which are most successful at eliminating feedback in a distance learning network:

Change the positioning and/or proximity of the microphones and loudspeakers relative to each other. For best results, loudspeakers should be positioned behind (not above) typical directional microphones, which are less sensitive to sounds arriving from the rear than to those arriving from the front.

Turn the loudspeaker volume down in the room. Lower volume levels, while making it more difficult for people to hear, reduce the tendency of the audio system to howl.

Reduce the number of open microphones (NOM), through the action of a live operator, or the use of Push-to-Talk microphones, or an automatic mixer. Reducing the number of open microphones has the same effect as turning down the overall volume of the audio system (but without the penalty of lower listening levels), thereby reducing the incidence of feedback.

Make the surfaces in the room less reflective by adding sound absorbent panels or coverings. In rooms with less-than-optimal acoustics, microphone-to-loudspeaker coupling may occur even though there is no direct path between the two. In this case, sound leaves the loudspeaker and is reflected off of the walls, ceiling, or floor, reaching the microphones indirectly.

Transmission Echo

Some types of transmission networks slightly delay the audio and video signals before or during transmission. This may be due to the time required for satellite transmission or the action of a device called a codec, which compresses the signal so that it can fit into a smaller (and less expensive) amount of space on the transmission line. When distance learning sites are connected over a network which induces some signal delay, the sound from the loudspeakers at the remote site can leak into microphones there, which causes an echo to be returned to the originating site. In other words, a talker in Classroom A speaks, his or her voice comes out of a loudspeaker in Classroom B and leaks into a microphone there, and that signal is transmitted back to Classroom A, where the talker hears an echo of his or her own words 1/4 to 1 second after having said them. If the leakage problem in Classroom B is not severe, the returned echo may be low enough in volume to be tolerable, but in almost all cases it is so annoying that conversation is impossible.

Various methods of dealing with echo have been devised; most of these were intended to minimize echo in long distance telephone lines. One type of device, called an echo canceller, monitors the incoming (or `Receive’) audio from other sites, and compares it to the signal that is about to be transmitted (the `Send’ signal). If the echo canceller detects the presence of the incoming audio in the outgoing signal, it creates a replica of the incoming audio and electronically subtracts it from the outgoing signal. This reduces the amount of echo, but does not completely “cancel” it. Notice that the echo canceller attempts to prevent the incoming audio from other sites from being sent back to them, but it does not do anything about the echoes that other sites may be sending to your site. For this reason, if one site on a network requires echo cancellation equipment, all of the sites on that network will almost certainly need it.

There are two general types of echo cancellers. The first, called a line echo canceller, is designed to remove electronic echoes from telephone lines; most long distance telephone circuits employ these devices. Line echo cancellers cannot significantly reduce the complex echoes which result from loudspeaker-to-microphone leakage in a classroom. The second type, called an acoustic echo canceller, is designed to reduce the chance of an echo being produced due to this leakage. Acoustic echo cancellers are commonly mistaken to be capable of removing the hollow sound associated with a room that is too reflective; no electronic device can do that. In fact, excess reflected sound makes it more difficult for the echo canceller to work properly, and reduces the degree to which it can reduce transmission echo.

Acoustic echo cancellers take time (1/10 of a second or more) to “learn” how to reduce echo in a particular room, and they have to go through this learning process whenever the path from loudspeaker to microphone changes. This might be caused by a wireless microphone user moving around the room, or microphones being turned on and off by an automatic mixer. During these “learning” periods, echoes will not be reduced.

Echo cancellers are expensive, and are not an alternative to good room acoustics and proper audio system design. At best, they can improve the sound quality of a distance learning network that suffers from echo problems, but they cannot make a classroom that has poor acoustics sound good.

Reflected or “Hollow” Sound
One of the most persistent and annoying problems with distance learning audio systems is the hollow sound – as if the talker is “at the bottom of a barrel” – caused by a room that is too reflective. Unfortunately, reflected sound cannot be removed by any type of electronic device; it must be kept out of the microphones in the first place.

The obvious solution, of course, is to make the room less reflective by covering surfaces with specially designed sound-absorptive materials. If changes to the room acoustics do not provide a sufficient improvement, the number of simultaneous open microphones (each of which adds a measure of reflected sound and background noise to the audio signal) must be reduced. Directional microphones can also reduce pickup of reflected sound, but only if they are positioned at less than the Critical Distance from the talker. Beyond the Critical Distance for the room, directional microphones offer minimal benefit. Finally, microphones can simply be moved closer to the talkers. Because the speech reaching the microphones will then be louder, the sensitivity of the microphone can be turned down at the microphone mixer, thereby decreasing its sensitivity to reflected sound and background noise as well.

The Broadcaster’s Secrets
Television news shows routinely feature live interviews by satellite with leaders around the world. Somehow, they never seem to experience any of the audio problems that plague many distance learning networks. What do broadcast engineers do that allows them to dodge the effects of feedback, echo, and reverberation? Here are three “audio commandments” that broadcasters live by:

Place the microphones as close to the talker as practical. In the studio, news anchors always wear a very small microphone (called a “lavalier” type) clipped to the necktie or jacket. In the field, reporters may wear a lavalier or use a standard handheld microphone. Because the camera shot is usually a tight close-up the microphone may not be visible, but rest assured that it’s no more than a foot or so away from the talker’s mouth. In situations where the talker cannot wear or hold a microphone, a long “shotgun” type microphone is mounted on a pole and held by a technician above and in front of the talker, just outside of the camera’s field of view. While effective for recording, shotgun microphones offer little advantage when used in a classroom. They, too, sound poor when used indoors at or beyond the Critical Distance of the room.

Use an ear piece. Broadcasters hear each other, the guests, the director, the commercials, and everything else through a small flesh-colored earphone worn in one ear. In high-noise environments such as sports events, the commentator wears a tight-fitting headset (to block out noise) with a boom microphone positioned just an inch or so from the mouth (for clear speech with minimal noise pickup.) Loudspeakers are rarely used, so loudspeaker-to-microphone leakage is eliminated. No leakage means no problems with feedback or echo. This is especially critical, given that remote interviews by satellite – which are subject to significant signal delays – often must be set up on a moment’s notice.

Use as few open microphones as possible. Fewer microphones pick up less noise, and require less time to set up and plug in. To optimize sound quality, an engineer constantly adjusts or “rides” the settings at the microphone mixer. You will rarely see more than four microphones being used at one time on television, but when more microphones are required than the engineer can keep up with, automatic mixers are frequently used.

Who Can Install the Audio System in Your Classroom

Hopefully, you are beginning to have a better understanding of the technical issues which must be dealt with in the design, installation, and use of a distance learning audio system. These may require more time or technical expertise than you can commit to the project. In any case, one of the following three options should help you to get a distance learning classroom installed at your institution:

Work with a qualified A/V consultant or sound system contractor. An acoustic or A/V consultant designs systems and writes what is known as a spec, or specification, of the equipment and room modifications required for the project. The consultant does not actually sell or install the equipment, however. A sound system contractor, working from the consultant’s design, sells, installs, and services the equipment. In some cases, the contractor both designs and installs the system. It is very important to work with firms that have experience with two-way interactive systems, such as teleconferencing or videoconferencing rooms or distance learning classrooms, because of the unique problems which arise in them as opposed to more typical public address systems found in churches or auditoria.

Purchase a pre-packaged system from a turnkey system provider. Companies which offer certain key elements of a distance learning system, such as fiber optic transmission equipment or service, sometimes “bundle” their own products or services together with those of companies that make the other equipment necessary (such as cameras, monitors, etc.) They are then able to market a complete distance learning system package for one price. In most cases, the actual installation of hardware is handled by a local sound system contractor.
Do it yourself. Institutions that have qualified technical people on staff with a knowledge of audio, video, and room acoustics, may be able to configure, install, and service a distance learning system without assistance. This may be a viable option if the system is a simple one – meaning that class sizes are small, echo is not a problem, and necessary modifications to the room acoustics are minimal.

FOR THOSE WHO WANT TO LEARN MORE

Additional sources of information

Architectural Acoustics by M. David Egan
(411 pages, hardcover; approximately $65.00) available from McGraw-Hill, Inc.
Complete review of audio theory, sound absorption and isolation, room acoustics, noise and vibration control, electronic sound systems, and more. Many useful examples, illustrations, tables, and equations.

Teleconferencing and Distance Learning by Patrick Portway and Carla Lane
(384 pages, softcover; approximately $50.00) available from Applied Business teleCommunications, San Ramon, CA 510-820-5563 tel/510-820-5894 fax
Collection of papers written by representatives from equipment manufacturers and industry associations. Chapters cover audio, echo cancellation, instructional design, transmission standards, training instructors, and more.

Audio Systems Design and Installation by Phillip Giddings
(574 pages, hardcover; approximately $60.00)
Comprehensive reference guide to audio system powering, grounding, wiring, and installation. Extensive discussion of equipment interconnection and noise problems.

Any Questions?
If you have questions about this document, contact support@shure.com.

Revision: 2/5/2007

What is MP3?

MP3 is nothing more than a file format for computers, no different than a document, spreadsheet, or, more closely related, a WAV sound file. For a computer to be able to store and play back a music file, the music needs to be “digitized.” In the same way that a scanner creates a digital representation of a photograph by reducing the image to a string of 1′s and 0′s that can be stored and interpreted by a computer, a computer sound card or other input device “samples” the incoming audio information and converts it to a similar string of 1′s and 0′s. Windows-based PCs commonly use the WAV (.wav) file format for storing audio information, since this format offers the same quality that you can achieve with a compact disc. Macintosh computers rely on the AIFF format for sound files.

At this point you may be thinking, “Then why bother with MP3? Can’t I just use WAV (or AIFF) files to store and send my music with my PC?” The answer is: (1) yes, you can, but (2) you don’t want to. The reason: file size. For example, to achieve CD-quality stereo audio, a WAV file will take up 10 MB (megabytes) of space for every minute of music. That means the average four-minute pop song will take up a whopping 40 MB! Not only does this rapidly eat up hard drive space, it makes downloading music a much longer process. Imagine a typical music fan trying to download the above song with a standard 56K modem – it would take over 90 minutes. That’s a pretty big time investment to get a four-minute song from a band you’ve never heard of! Enter MP3.

The term MP3 is short for “MPEG Audio Layer 3″ (For the curious, MPEG is an acronym for Moving Picture Experts Group). In addition to being a file format, MP3 also refers to a standard for compressing audio files to reduce their size. Therein lies the primary reason for using the MP3 format: smaller files. Sound files can be reduced by as much as a factor of 12 and still retain a high level of audio quality. Is it CD quality? Not quite, but it’s pretty close. Using MP3 format, the 40 MB WAV file from the previous paragraph can be reduced to less than 3.5 MB. The methods employed to reduce file size are called “perceptual audio coding techniques.” (Huh?) Basically, the brilliant engineers who developed the MP3 standard found a way to reduce file size by “throwing away” the bits that contain information relatively useless to the way humans perceive sound. (Of course, there are other digital audio formats that use similar techniques. For instance, MiniDisc uses ATRAC compression to reduce file size, making it possible to fit 74 minutes of near-CD quality music on a tiny MiniDisc. But we digress…) Getting back to MP3, with the sound file now reduced to 3.5 MB, the download time has dropped to less than 10 minutes with a 56K modem.

The incredibly small file size of MP3, combined with high quality audio, has led to a virtual explosion of music available on the Web. Here’s a quick list of things you’ll need to get dialed-in to the MP3 phenomenon.

First, get an Internet connection. AOL, local ISP (Internet Service Provider), cable modem, DSL, office computer (just kidding!) – it doesn’t matter what you choose, just get one. The faster, the better.

Second, make sure you have a sound card installed on your computer. In general, if your computer makes noise (besides the fan or start-up “beep”), you probably have one. Most newer systems come with the sound card pre-installed.

Once you’re connected, download a MP3 player. These are required to play MP3 files. There are many available, but some of the more popular players includeWinamp andSonique. You can also download virtual “skins” for these players, which change the on-screen look of the player, and visualizations that create graphic representations of the music. Windows Media Player, Apple’s Quicktime 4, and Real Player will also play MP3s. The official MPEG site, www.mpeg.org, also has several players available for download. Offline, several Walkman-style portable MP3 players, such as the Diamond Rio, have appeared in recent months. These players allow you to load MP3 files into temporary memory and take your music with you.

The next step involves downloading MP3 files to play on your computer. There are literally hundreds of places to get MP3s from on the Web. The obvious place to start iswww.mp3.com, but if you wish to find files in other locations, searching “MP3″ on any search engine will yield endless results. In fact, in 1999, MP3 replaced another popular three-letter word as the most searched-for term on the Internet. See the end of this article for an extended list of MP3-related sites.

Now that you’ve experienced MP3, let’s discuss how to use this format to get your music online.

How do I make an MP3?

Musicians who want to create MP3 files of their songs fall into two categories: those who have their music recorded onto compact disc, and those who don’t. If you already have a finished CD, skip the rest of this section, and download one the CD “rippers” listed in the next one. If your music is yet to be recorded, read on and learn!

The key to a quality MP3 is a quality recording. MP3 uses a “lossy” compression scheme to reduce the size of the audio files, which means that bits of the sound are thrown away, or “lost.” What this means is that, while the differences are slight, a less than ideal recording will be degraded even further by the MP3 encoding process. With that being the case, it’s therefore important that you use whatever means necessary to achieve a high-quality recording. The how’s and why’s of creating a good recording are beyond the scope of this article, but microphone choice and placement are critical to achieving good results.

Microphone choice is highly dependent on the instruments you are recording, as well as the style of music. If you use an inexpensive microphone that doesn’t capture your sound the way you envision it, no amount of “tweaking” later on in the recording process will restore it. At the very least, a decent quality condenser microphone and a couple of multi-purpose dynamic microphones will get you through most general recording situations. As your needs and recording ability grow, so will your microphone collection. For help in choosing which microphones to use, see the Shure Microphone Selection Guide.

To learn more about microphone placement and technique, see Microphone Techniques for Music: Studio Recording, published by Shure. This free publication is a great resource for help with the placement of microphones, as well as insight into the more technical aspects of microphones and how they work.

Choosing a recording format is also an important task, and one that has become a bit daunting lately. There are many different ways to record your music, each with its own set of benefits and drawbacks. Unless you plan on recording at a professional studio, stick to one of the many digital recording formats available today.

The traditional tool of the home recordist for the past 15 years or so has been the cassette-based 4-track studio. While a convenient tool for songwriting, achieving a professional sounding recording with the cassette medium is nearly impossible. Pro studios that use analog recording mediums make use of expensive multitrack recorders that use 1″ and 2″ tape, which are vastly superior to cassettes. Since this gear is prohibitively expensive for the independent musician, go digital.

A number of affordable digital formats have hit the market in recent years, and most far exceed the limited sound quality of the cassette. If you’re comfortable with the 4-track format, investigate MiniDisc multitracks, or stand alone hard-disk recorders. The MDM (Modular Digital Multitrack) formats, such as ADAT and Tascam DA88, have revolutionized the home recording market. If computers are your thing, then digital recording is as simple as getting a decent sound card and multitrack recording software. Some sound cards will allow you to connect microphones directly to their audio inputs. You’ll also need plenty of disc space for storage. See the Shure Technical Bulletin, Interfacing Professional Microphones to Computer Sound Cards, to learn more about connecting microphones to your computer. For additional help in choosing the right recording format, check out a few of the many magazines and Web sites dedicated to home recording and project studios.

The music is recorded. Now what?

Now that your music is recorded, it’s time to make an MP3. At this point, you need to get the songs into your computer. There are several ways this can be done; choose the one that seems most appropriate for your situation.

If you have a finished CD of your music, download a “ripper” program and use it to digitally “rip” the audio off the disc. Steambox Ripper, Play & Record, and MusicMatch are “rippers” for Windows; SoundJam MP works for Macintosh. This procedure requires a CD-ROM drive installed in your computer. If you don’t have a CD-ROM drive, but your sound card has a digital input, you can use a CD player with a digital output to record onto your computer (see below).

If you used a computer to record, you’re most of the way there. Be sure to mix down to a single stereo sound file for conversion to MP3 (the format does not support conversion of multitrack audio beyond stereo).

If you used an external digital recorder, such as a 4-track MiniDisc or hard disk system, those units usually come equipped with a digital output. If your sound card has a digital input, use it to transfer the audio digitally from the recorder. The two most popular types of digital interfaces are S/PDIF, which uses RCA-type connectors, and optical, which uses a special fiber-optic cable. If your recorder and sound card digital interfaces don’t match up, there are external converter boxes that will convert between the two formats. There is also a third type of digital interface, AES/EBU, which uses XLR connectors and is only found on higher-end, pro gear.

None of the above: If worse comes to worse, you can always record through the analog input of a sound card. Be sure the input record level is set as high as possible without clipping to allow for the most accurate recording. This method will work for CD, MiniDisc, and (yuck!) cassette. But whenever possible, work in the digital domain.

The next step involves yet another piece of software, commonly referred to as an MP3 encoder. This handy little piece of programming does all the hard work involved in converting a sound file to an MP3. You still have some choices to make, the most important of which is “bit rate.” The bit rate you choose determines the size of the file and the audio quality. The standard on most MP3 sites is 128 kb/s (kilobits per second). It is not CD quality sound, but it is the most common “encoding rate” used. There are many different programs that will let you convert audio into MP3 format: MusicMatch, Real Jukebox, and Streambox Ripper are just a few. Most of these encoders are freeware or shareware. You can browse a variety of encoders at MP3.com or the Shareware Music Machine. A few multitrack software programs also include MP3 encoding as part of their feature set. N-Track, a shareware multitrack recording program gives you the option to create an MP3 file as it’s creating a stereo WAV.

Lower encoding rates yield smaller files, higher encoding rates result in bigger files. For example, a typical 3-minute song encoded at 128 kb/s will be around 3 MB. If you were to encode the same song at 64 kb/s it would be 1.5 MB. At 192 kb/s it would be about 4.5 MB. Audio quality generally increases at higher bit rates, but people downloading songs with a dial-up modem will hesitate to download files over 5 MB. Conversely, you wouldn’t encode a great song at 64 kb/s, because the end result would pale in comparison to the original. Most MP3 sites prefer your music be encoded at 128 kb/s.

Depending on the software you’re using, several more options present themselves that will affect the outcome of the encoding process. For more detailed information on encoding MP3s, see: homerecording.about.com/entertainment/ homerecording/library/weekly/aa121299a.htm.

What do I do with my MP3s?

Congratulations! With your newly encoded MP3 files, everyone will be able to enjoy your music. After you upload, that is. In order for people to hear your music, they need to be able to find it. As mentioned earlier, there are tons of places on-line where you can distribute your MP3s. But it’s up to you to get them there. Here is a quick laundry list of potential places to put your tunes:

www.mp3.com

www.musicbuilder.com

www.iuma.com

Each site has its advantages, disadvantages, and idiosyncrasies. And of course, new ones are springing up all the time. We recommend spending some time at each one, learning what you like and don’t like, what the upload process is, and if any fees are involved.

A note about legal stuff.

All of this is fun until someone loses an eye – or a royalty. MP3 has opened the door for an efficient, free exchange of music on the Internet. But be warned, uploading OR downloading unauthorized MP3 files of someone else’s music is illegal. Period. Feel free to upload as much of your own original material as you wish; it’s a great way to reach a lot of people. “Ripping” copyrighted songs from your favorite CD and making them into MP3 files for your own personal enjoyment is also perfectly legal – your computer becomes a virtual jukebox. But if a friend copies those same MP3 files for their use, the artist has just lost a well-deserved royalty. The losses compound if the files are posted on a web site for anyone to use. (Napster is being sued for facilitating this practice.) The RIAA (Recording Industry Association of America) is already moving to restrict the MP3 format through their Secure Digital Music Initiative, which is developing a standard for secure distribution of music on the Internet. Visit www.riaa.com and www.sdmi.org for additional information.

The following article is an excerpt from Shure Notes, Issue #16(March 2006).

Podcasts. They’re getting a lot of attention these days. Is this the audio equivalent of blogs, where commentary can be shared over the Internet – or a powerful tool that puts broadcasting within the reach of anyone with music, a message and basic gear?

In this article, we’ll take you through the basics – what it is, who’s using it and how you can get started.

But First, What is It?

Here’s how one expert describes it:

“Podcasting is a method of publishing files via the Internet, allowing users to subscribe to a feed and receive new files automatically. It became popular in late 2004, intended largely for downloading audio files onto a portable MP3 player. Listening to podcasts does not require a portable player and it is not traditional ‘broadcasting’ to a mass audience at a fixed time.

The word “podcasting” is a linguistics blend coined in February 2004, combining “broadcasting” with the name of Apple Computer’s iPod audio player (although podcasting was not invented by Apple, nor do podcasts require a portable player or Apple software).

It is distinct from other types of online audio delivery because of its subscription model, which uses the RSS 2.0 file format. Podcasting enables independent producers to create self-published, syndicated “radio shows” and gives broadcast radio programs a new distribution channel. Listeners may subscribe to feeds using “podcatching” software (a type of “aggregator”.) which periodically checks for and downloads new content.”

*Source: God’s iPod

How to Get in the Game

Now that you know what a podcast is, you need to understand what it’s going to take to create one – or a series – of your own.

We’re going to look at three basic steps:

1. Plan
2. Produce
3. Post

Our guide for a stretch of this trip is Jason Van Orden, musician, educator, audio tech and practicing podcaster. Among his highly regarded podcasts: The Podcasting Underground, Internet Business Mastery and Gothamcast, rated as “New and Notable” in the Yahoo! Podcast Directory. His excellent how-to-podcast-tutorial.com is the foundation of our step-by-step guide (and will provide you with more detail than we’re able to here in Shure Notes).

Step 1: Plan

If you’re a musician, you know how to put a set list together. But if you want to produce a podcast that will attract and retain listeners, a little planning will help keep you and the podcast focused.

Ask yourself and your team these questions:

Who will be doing the podcast?

Some podcasts have one host, others have a team and still others feature a “cast”. The advantage of having multiple performers is:

• It is generally more engaging for your listeners.
• It spreads the content and performance responsibilities across several individuals.

What segments will your create?

Think about the programs you usually listen to or watch. Most all of them, particularly radio, have a format. Having a structure for your podcast will make it easier to plan and produce, plus your listeners will know what to expect and they’ll look forward to it. Here’s an example:

• Introduction (Theme Song)
• Welcome Message
• Announcements
• Song Intro
• Song
• Song Intro
• Song
• Music News
• Song Outro

How long will the podcast be?

You don’t have to fit your podcast into a specific time frame, but remember this: Your podcast should last as long as you can hold a listener’s attention — and that’s why many podcasts are about 20-30 minutes in length.

One of your goals should be to leave the listener wanting more, not looking at his or her watch. Remember, too, to build excitement for your next podcast.

How often will new podcasts be released?

Successful podcasters understand what bloggers and publisher have know for a long time – they are creating communities. Having a consistent publishing schedule will help you build listener loyalty.

These are format questions that will help keep you and your team on track. As an evolving medium, podcasts are dynamic and yours will change over time. There aren’t very many hard and fast rules, except for this one: If you use music or material that is not your own, make sure you are observing any relevant copyright laws. Get permission and better yet, get it in writing.

Step 2: Produce

Now that you have a format and a plan, you’re ready to think about the production process. This involves:

• Having the Right Gear
• Choosing a Recording Location

Let’s look at these one at a time.

Having the Right Gear: HARDWARE

To get started, you need a computer with broadband access, a microphone and headphones.

Computer

You will probably record and edit your podcast on your MAC or PC. Most computers that have been released in the last few years can be used for podcasting. The real demands on your computer will be its ability to record and process the audio.

Broadband Internet Connection

Not gear, but a necessity. To upload your podcast to the Internet and update your site, you’ll need a DSL, cable or T1 Internet connection.

Microphone

Whether you are recording a vocalist, instruments or spoken word, you’re going to need a microphone. Once again, your options are pretty much determined by what you’re recording and how much you have to spend. The good news is that you probably have mics on hand that will work well for podcasting.

Since every microphone has a distinct sonic signature, along with its own characteristics in terms of transducer type (condenser or dynamic) and polar pattern (unidirectional, cardioid and supercardioid), it’s important to understand the differences. Click here for information on microphone types.

In order to make the right choice, decide which is the most important element in your podcast. It’s probably the voice. If so, a large-diaphragm condenser microphone like the KSM 27 might be best. However, a fairly neutral sounding cardioid pattern condenser mic like Shure’s SM58 can work well on a wide variety of sound sources. Experiment with mic placement to get the best results.

Earphones

In the most basic podcasting set-up, just about any headphones that plug into your computer will get the job done. Keep in mind, though – an important part of the process involves listening to your podcasts. Not so long ago, this required wearing a heavy headset to block out room noise.

Technology has made that cumbersome gear a thing of the past with the introduction of high performance, sound-isolating earphones that you can use when recording – and for listening to podcasts on your iPod or MP3 player, the way most of your listeners will.

Here are two from Shure:

Starting Out

The Shure SE110 Earphones feature a studio quality, sound-isolating design. They come with a fit kit for personalized, in-ear placement. You can find them at your local Shure dealer or purchase them directly from the Shure online store (US Only) for around $120 (MSRP) a pair.

Stepping Up

The Shure SE210 Earphones offer sound isolating design with high-definition micro-speakers and extended frequency response for studio-quality sound. These cost about $180 a pair.

MP3 Player

When you post your podcast, download it through the feed into your MP3 player just like your listeners do. You’ll be able to perform a little quality control and also see how the information from the MP3 files is displayed – does it look the way you want it to?

Listen to other podcasts. You’ll gather ideas for your own shows and stay current with podcasting and what other podcasters are doing.

Having the Right Gear: SOFTWARE

You will need software for recording and editing your audio. There are many choices from ProTools, Acid, Sonar, Live and GarageBand (which offer the added benefit of royalty-free audio loops) to Audacity, which according to Jason Van Orden, has become popular with podcasting newbies and is available for free.

According to “The Art of Podcasting” in the December issue of Electronic Musician, “dedicated podcast-creation programs are springing up all the time. For Windows, there’s CastBlaster, Propaganda and ePodcast Creator. In addition to organizing and triggering audio clips, these programs export MP3s and the specialized text file that defines the podcast. They can also assist with file upload.”

You’ll need to convert your podcast to MP3 format before uploading it to the Internet. Converting your audio to MP3 makes the file size smaller and easier for others to download and listen to. Again, there are a number of free programs available for download, including iTunes and LAME. LAME appears to be the podcaster’s encoder of choice and offers an impressive array of features (for Mac and PC).

Choosing a Recording Location

If you have some recording experience, you’ll want to follow the same, successful techniques you’ve used in the past. For the rest of you – some useful tips:

Scout a location.
Have a place set up – preferably near the gear you’ll be using – that’s ready to go when you and your team are.

• Choose a space that’s quiet and free from distractions. Minimize as much background noise as possible.
• Turn off fans, additional computers, air conditioning units and telephones.
• Post a sign outside the door alerting passersby that you are recording.
• Think about room acoustics.

Closet Space. Recording Space.

“One of the best tricks I’ve found for creating a quiet recording space is to open the closet door, throw a large blanket or sleeping bag over the wide-open door and position the mic so that the dead spot of the mic is pointing right back into the open closet. The more clothes in the closet, the better. Remember, as you sing or speak – not only are you picking up the sound of your voice – you’re picking up any reflections in the room coming back from behind you. Singing into a closet is just like singing in a studio GOBO – it absorbs many of the reflections and can give you a darker, tighter sound.”

- Greg Riggs, Shure Associate

Step 3: Post

Ready to upload? You’ll need an FTP program. Once your podcast is ready for primetime, you’ll need to upload it to the Internet. SmartFTP is free for personal, educational and non-profit use.

If Rachel Can Do it, So Can You.

According to Business Week, “8 year-old Rachel Patchett hosts Rachel’s Choice, a weekly podcast in which she plays a Christian song and reads a bible verse. Up to 1,500 listeners tune in every week. Of course, it helps that her father is the man behind The GodCast Network, a portal offering 14 different religious broadcasts. There is a wealth of information available on the subject – much of it on the Internet, a good resource since the podcasting world is growing and changing so quickly. There’s even a podcasting organization – the Association of Music Podcasting. There are literally hundreds of sites that offer everything from weekly podcasting tips, to free software, podcast directories and places to upload your podcast. And of course, there’s an aftermarket of podcast developers who will do the work for you.

You have the gear. Now you have the production basics. Consider this: In 2005, a respected research group predicted that the U.S. podcast audience will climb to 56 million by 2010. By that time, three-quarters of all people who own portable digital music players will listen to podcasts. Talk about expanding your audience.

Visit Jason Van Orden’s site at: www.how-to-podcast-tutorial.com for a more thorough step-by-step guide to creating your first podcast. We also recommend David Battino’s “The Art of Podcasting” in the December 2005 issue of Electronic Musician. Like many of the websites dedicated to podcasting, there’s a helpful directory that includes podcast, hosting, resources, reading and software sites.

Five Reasons Why

• You already own most of the equipment. If you have a computer, a broadband connection and a microphone, you’ve got the basic gear.
• You will reach a wider audience. It’s all about reaching out, right? Not only can you stay in touch with your fans (as an example), you have the potential to reach an audience far beyond geographic boundaries. Think national. Think global.
• You’re in control.
• One of the great advantages of podcasting is its inherent flexibility – you can publish your podcast as often as you want (every day, every week, every month) and it can be as long as it needs to be. You’re not limited to a format. The fact is, you’ll be developing a format of your own. Talk. Music. Talk and music.
• It’s automatic.

Once you’ve developed your content and listeners have subscribed, the foundation is built. When you post new content, it’s automatically downloaded and transferred to your listener’s MP3 player. Because listeners have subscribed to your podcast, they’re motivated to receive your message. It won’t get lost like SPAM e-mail — and because your podcast is delivered over the Internet, it’s inexpensive.
This is “Theater of the Mind”
Very few of us can recall the radio days of our grandparents, when listeners, not distracted by the kinds of visual imagery that assaults us today, unleashed the power of imagination to experience “theater of the mind”. Podcasts can do the same thing. This is intimate and impactful – a medium that delivers a very personal listening experience.

More Length = More Storage
The longer the show, the larger your MP3 file and the more website bandwidth is required. Depending on your situation, you may need to contact your ISP.

Do You Really Need a Pop Filter?

If you’re not familiar with recording, you may not know that the popping (or plosive) sounds that are made when a speaker uses words with “p” or “b” can be annoying to listeners. A pop filter is usually made of nylon cloth stretched around a frame, threaded to screw on a microphone stand. (A cheap pop filter can even be made from a pair of stockings and a coat hanger in an emergency.) This filter is placed in front of the diaphragm, between the microphone and the vocalist’s mouth.

Podcasters and Aggregators

Sounds like a game of ‘cops and robbers’, right? These are terms that refer to what’s required for a listener to download a podcast. Here’s the good news: any digital audio player or computer can play podcasts. On the other hand, if listeners wish to subscribe to your podcasts, they’ll need podcatching software (an aggregator) that checks for and downloads new content directly to their audio player or computer, iTunes and Windows Media Player, both free.