Stereo Miking Basics
he following article is an excerpt from Shure Notes, Issue #25. Updated June 23, 2011.
If you want to capture a more natural sound in your recordings, it’s time to learn a few fundamentals of stereo miking.
Early on, these techniques were developed to approximate the sound we hear in our own two ears. Stereo recordings give the listener sound images that correspond to the location of the instruments in the recording session – left to right and front to back. They provide a picture of the recording space’s acoustics and capture sound source characteristics without the tonal imbalances that mono close miking can sometimes produce.
Stereo miking offers an open sound that is an alternative to multi-track recording.
Using just two or three microphones, stereo miking is still the preferred method to record classical music and small ensembles ambiently. In this article, we’ll explain four of the most popular stereo miking techniques, illustrate them with images of mic set-ups from Shure’s Performance Listening Center and provide audio clips that will amplify the critical listening differences.
Stereo Microphone Techniques
Every recording situation is different. Room acoustics vary, the instrumentation changes, even the type of music and tempo can influence the sound you’re trying to capture. You’ll probably want to test more than one of the following techniques (and then make your own adjustments) to get the recording you want.
Unless you’re one of the fortunate few with a well-stocked mic locker, you don’t need a lot of expensive gear to get started. In fact, a couple of inexpensive cardioid mics will get the job done. Just make sure they are the same make and manufacture to minimize differences in their sonic signatures. What’s most important here are your own critical listening skills, since stereo recording is an attempt to replicate the way your personal transducers (those ears of yours) process sound.
Here are four of the most typical stereo miking techniques.
Keep in mind that stereo miking, just like any other audio exploration – whether its composing, performing, doing live sound or recording — is just that … a journey and an opportunity to experiment.
It is completely subjective, so try different techniques, borrow microphones if you need to and play with angles and positions to achieve the recorded sound you’re after. Be careful about the most basic of basics – tightening stands and mic clips. Take your time. Be meticulous and the results will be more than worth your effort.
Tips from the Pros
“My favorite stereo miking technique changes with the application. For a larger vocal group or choir, I like ORTF or X/Y plus an extra wide spaced pair to capture the outer edges of the group. For drum overheads my favorite is definitely X/Y. For me, it centers the snare in the stereo picture better than a spaced pair and also is less prone to phase issues because the capsules are so close together. For acoustic piano and hand percussion, I like ORTF for its wide picture of the stereo field.” –Kevin Becka, MIX Magazine Technical Editor
“One stereo mic technique I seldom see employed live is the good old X/Y pair over the drum kit as overheads. Properly utilized, an overhead X/Y pair gives you a very big stereo image that translates across the venue quite nicely, and collapses down to mono – perfect for your matrix feeds and whatnot. Get yourself a nice sturdy stand and a couple KSM44s and give it a shot. Also an extremely wide pair of SM81s are great for realistic room/audience mics for your multi track live mixes. Place them as far downstage left and right as possible. Sometimes the talent likes a little in their in ears as well. Gets rid of that isolated feeling in the ear buds.” –Zach Mishur; Guitar Player, FOH Engineer
“In tracking mostly vocal groups, I use two different setups for stereo recording. It all depends on the size of the source I’m capturing. If the source is no wider than 10-15 feet, I’ll go with two small diaphragm condenser mics in an XY configuration, making sure each capsule is at a 90 degree angle to each other. If I am trying to capture a larger source, like a chorus or orchestra, I’ll use a Decca Tree style which is 3 large capsule condenser microphones in a triangle configuration, 2 mics three units apart, and the third centered between the two and 1 unit forward toward the source. Always keep a 1 to 3 ratio between the 3 mics to limit phase cancellation. Then I use two other small condenser mics on the outside edges of the source on the same plane as the 3 mics on the Decca tree to add to the stereo image.
I’ve used this in Germany for a Symphony concert with the vocal group, Take 6 for an outdoor concert in Berlin. The six guys were amplified through individual handheld mics and supported by the Decca tree, 5 mic setup on the symphony. It resulted in an extremely natural representation of the symphony, while giving clarity to the 6 vocalists. The only true issue we had was that our in-ear transmitters were on illegal frequencies and broadcasting on police radios around the city. I thought they would have liked a 10 time GRAMMY® winning group breaking up the radio waves and adding to their crime fighting days. But, no. They threatened to shut the festival down.” –Tony Huerta, GRAMMY® Award-Winning Producer
“While the bulk of my work as a producer and engineer involves recording vocals or other mono sources, I recently had an opportunity to use my pair of Shure KSM-141s in a fairly unstructured recording environment. A composer client of mine booked time in a high-end furniture showroom in New York City to record some of his contemporary classical arias with a pianist (the showroom just happened to have a Steinway) and an array of vocalists. I arrived with my laptop, a mic stand with a stereo bar mount attached, my KSM141s and a set of Shure’s SE530 in-ear monitors to be certain my sound source was being accurately represented.
In this instance, I used a modified X/Y pattern where I pointed one mic at the partially closed piano and the other in the general area of the vocalists. In order to get a proper vocal balance (given that the number of vocalists on any given piece ranged from one to twelve!) I had the softer/lower voices closer to the vocal-directed mic and the louder/higher voices a bit further back. In the end, by adjusting the left and right levels (in my mix) I was able to get a nice, full stereo blend of the vocals and piano that accurately captured the spirit of the room and the performance.” –Cliff Goldmacher; Recording Engineer, Studio Owner
“My engineer, Brian Peters, and I love to experiment with colors and sounds and upon reflection on how three of our last solo CDs were recorded, we realized we’ve actually never used the same technique for any two recordings. Our approach to each new CD was always borne out of new ideas and inspiration, as well as reactions to whatever we’ve done in the past – gleaning some things and discarding others.
For “StereoNucleosis” (WERTICO – 2004) we settled on a configuration with two KSM 32s on either side of the drum kit, at arm level, facing inward at the kit, almost like room microphones. It gave a very spacey asymmetrical sort of sound, but it captured the spirit of what we were trying to do for the record, so we went with it. On a few tunes, we panned both microphones center to make the drums punchier for rock-beat type grooves.
For “Ampersand” (Brian Peters & Paul Wertico – 2007) we did a more traditional spaced pair above the kit, observing a line of symmetry and capturing everything in a balanced way, but then for one song (“The Tundra”) we decided to apply cymbal mutes (Pro-Mark X-Mutes) to shorten all of the cymbal sounds on the kit in comparison to the drums and we discovered that the entire kit sounded pretty good just through the overheads. So we kept everything mono (sometimes alternating mics, sometimes using both at the same time) and we threw a huge amount of compression with an ultra fast release across the entire drum bus to bring out the cascading decays of the different elements of the kit, later adding in a little bit of kick and snare mics to make it meatier.
For “Impressions of a City” (Paul Wertico’s Mid-East/Mid-West Alliance – 2009) an X/Y overhead configuration was used, but during mixdown, the sonic image of the kit felt too shallow and wide, so we panned the overheads in reverse orientation from the stereo image of the tom mics, which made the kit suddenly feel more three dimensional and spatially deep.
Often, after getting the sounds for all the close mics, we’ll set up multiple configurations of overheads and listen to how they sit in a mix, and how they sound by themselves during solo drum pieces. We’ve used the Blumlein technique for realistic binaural recordings that capture intricate patterns being played across a ride cymbal, we’ve used an M-S configuration when we wanted to capture the entire kit in an interesting sounding space but wanted to have control over the balance of the natural reverb during mixdown, and sometimes we’ve recorded the cymbals and drums separately when we wanted to EQ the cymbals a certain way but not affect the sound of a brush part on the rest of the kit.
Overall, the most important (and rewarding) thing is to keep continually trying new things and to avoid just settling on some ‘tried and true’ method that might have been instituted after trying one thing you read on the internet that someone said is “the best” method for everyone.” –Paul Wertico, GRAMMY® Award-Winning Drummer
Several of the most common stereo miking techniques are known by different names. That can be confusing for the newbie recordist.
(Also know as X-Y Pair) Microphones angled apart with grilles touching.
A spaced microphone variation commonly used for orchestral recording. Developed as an A-B method adding a center fill, the technique was developed in the early 1950s by a team at Decca Records to provide a stereo image.
A common variation is called the ORTF system, so named for the French Broadcasting Organization that developed it. Microphones angled about 110° apart, often with capsules about 6″ to 7″ apart.
Mics spaced 3-10’ apart, pointed forward.
Also known as M-S. Cardioid mic pointed forward, bi-directional mic side-pointed.
Shure Recording Microphone Lockers
If you need a basic selection of microphones to get your studio up and running, here are a few selections based on type.
Basic Home Studio
(Overdubs, vocals, acoustic guitar)
- SM57 (2)
- SM27 (1)
Advanced Home Studio
(Tracking, drums, overdubs, vocals, guitar)
- SM57 (3)
- SM27 (1)
- KSM137 (2)
- Beta52A (1)
- A27M (1)
Type of recording: Commercial (Tracking, drums, overdubs, vocals, guitar)
- SM57 (4)
- Beta52®A (1)
- KSM137 (2)
- KSM32 (2)
- KSM44A (1)
- SM7B (1)
- VP88 (1)
Here’s where to find more comprehensive information on the subject of stereo miking and even more stereo miking techniques.
Bruce Bartlett, Recording Music on Location
F. Alton Everest, Critical Listening Skills for Audio Professionals
Ron Streicher & F. Alton Everest, The New Stereo Soundbook