Using Stereo Overhead Miking Techniques to Supplement a Multi-Miked Drum Setup
Contributor: Mike Major
I have always felt that the best drum sounds are achieved when there is a seamless marriage of the close-mics and a stereo pair of overhead mics. There should be but one drum sound, not a collection of mics that are mixed together. It’s not as simple as placing a mic on each drum and two more above the kit, and bringing up the faders. It takes work. It takes awareness and understanding of how the sound propagates from the drum and out through the room, and how the mics respond to that phenomenon. Each mic is reacting to every percussive event at a different time, from a different angle, with a different frequency response and slew rate, and with a different amount of ambience. If you break it down (and you should), it’s a wonder that you can ever get all of the mics to work together harmoniously. But you can. Really.
The Importance of the Overhead Mics
The overheads are the unifying element in any drum sound. Don’t think of them as cymbal mics, but more as “everything” mics. If placed correctly, the overheads will capture the entire drum kit, in phase and with the same basic frequency balance and tone.
Be aware that even if you plan to use a substantial amount of the close-mics in your drum mix, you still have to get the overhead placement right. The overheads will cause the sound of your close-mics to change no matter what, so you might as well make sure that the change is for the better. Even if you go so far as to filter all of the lower frequencies from your overheads (a common practice for some), there will still be noticeable interactions with the close mics.
Overhead Placement Techniques and Considerations
I always start the process of getting a drum sound with the overhead mics. I spend some time listening to the kit in the room while trying to formulate the best approach to make the overheads clean, clear, and focused. I listen for a balance between the cymbals and drums that makes sense with what is happening acoustically. To achieve a balance requires thinking about how the overheads will bisect the drum kit left to right, front to back, or top to bottom.
You need to consider the drum kit in all three dimensions to exploit the available choices.
Overhead Mic Placement-Left to Right
You could start by simply centering the overhead mics over the drum kit using an X/Y or ORTF pair (note: my first choice for this task is a large diaphragm cardioid condenser so that mic type will be assumed throughout this post. Any condenser or ribbon mic is well suited for the job so use what you have or prefer!). The drum kit can be split right down the middle, as shown in Figure 1. This gives you a nice spread of the toms and cymbals, and the kick drum will be pretty close to the center of the image. This is all good, but you may also notice that the snare is entirely on the right side (in this image, anyway). This will create problems with your stereo image when you add the snare mic to your drum mix.
If you pan the snare mic to the center (which is common and preferable) then you will be confronted with sonic ambiguity. The center-panned snare mic is obvious and definite, but the overheads will try to pull the snare more to the right. Even if you use a disproportionate amount of the snare mic in the mix, the overheads will still tell your ears that something is amiss. There is a way to deal with this scenario.
I prefer to create a new “audio center” that is offset from the physical center of the drum kit. Looking down on the kit from above, I draw an imaginary line through the kick drum and on through the center of the snare drum (see Figure 2). The audio center is the new guideline to use as you place your overhead mics for adequate coverage. If you balance the levels of your overheads in a way that keeps the snare and kick centered, you will have a strong, coherent picture when you add the kick, overheads, and snare mics to the mix. This anchors the drum sound whether you use more of the close-mics or the overhead mics. The two components, near and far, are in agreement.
You should try to make sure that everything still makes sense in the new, modified stereo image, including the toms and cymbals. The panning that exists naturally in the overheads guides you as to where to pan your close-mics. You want it all to match. When it matches, the stereo image remains solid, no matter what you do. Nonetheless, if there is a slight disagreement between the toms and the OH panning, it does not upset the balance the way it does with the snare. This is due to the fact that the toms are rarely as present in the overheads as the snare and cymbals are. This gives you a bit more latitude with their panning.
Using this technique tends to create a wider spread between the toms and cymbals. This leaves more room in the middle of the mix for important things like the bass guitar and vocals. I have also observed that most right-handed drummers have more “stuff” on the left side of the kit (as you’re facing it); so this offset creates a better balance left to right and makes for a more interesting stereo image.
The biggest drawback to this approach is that the hi-hat and right side crashes end up having much less distance to travel to the OH mic than anything does on the left side. You may have to place the right mic higher than the left mic to compensate for the difference. Naturally, if this were the case, you would have to abandon your X/Y or ORTF pair. You can, however, measure the distances from the snare to each overhead mic to ensure that the time arrival of the snare is the same in each overhead mic. The kick may end up with a bit of a bias to the left side but it does not create the same problem that the snare can create. In a perfect world you should try to get the kick as centered as possible, but centering the snare is crucial.
Overhead Mic Placement: The Mic Angle and Your On-Axis Focal Point
Adjusting the overhead mic angle is another tool to get your balance right. You should keep the front of the mics on axis with the kit as you move them forward or backward. What you want to be “on-axis” is dependent on what you choose as the focal point for the overhead mics.
If you are looking for a more cymbal-centric overhead balance, the cymbals will be the on-axis focal point, as shown in Figure 3.
If you want more drums and less cymbals, the drums will be your target, as shown here in Figure 4.
You can also aim at a point in between the drums and the cymbals to capture a balance of both (see Figure 5).
I like to keep the snare as much on-axis as possible even while aiming for the rest of the kit. The snare is so important to the drum sound that it should be captured by the sweet spot of the mic whenever possible. The distance of the OH mics from the snare makes this fairly easy since the polar pattern continues to widen as it gets farther from the mic capsule.
Overhead Mic Placement: Front to Back
As you might expect, the balance changes dramatically as you move the mics from front to back. Moving the mics toward the front of the kit will push them closer to the cymbals and the rack tom. Pulling them back will pull them closer to the snare, floor tom, and hi-hat. These adjustments move the drums and cymbals in and out of the mics’ polar patterns, so pay attention to how the tone and balance changes when you move them (as in Figure 6).
I prefer to increase the angle of the mics as I move farther back so the fronts of the mic capsules are always facing toward the drums. You can go as far as having a pair right above the drummer’s head, aimed back toward the drums. This can capture an image that is much like what the drummer hears while she’s playing. If you move the mics to the front then, again, the cymbals will be in the foreground.
To maintain this orientation of the mic you should adjust them as if they were mounted on a track that moves in an arc above the drum kit, to the front and the back (see Figure 7).
Overhead Mic Placement: Up and Down
The final dimension involves adjusting the mics up and down (see Figure 8).
The up and down adjustment can be used for several critical effects:
- It can be an excellent ambience adjustment. As you bring the mics lower and closer you lose a bit of the ambience; go up and you get a bit more roominess.
- It can be a stereo width control. As you bring the mics down and move them closer to the cymbals and drums, you must aim the mics farther away from the center to keep everything on-axis. Naturally the image gets wider. This does not work well with an X/Y pair if you exceed 135 degrees between the capsules.
- You can vary the heights of each mic independently to compensate for differences in time arrival from different parts of the kit. As I said earlier, some drums and cymbals are going to end up closer to the overhead mics than others. To even the arrival times you can place the two overhead mics at two different heights, as few as 2–3 inches or up to 8–10 inches if necessary. This will solidify the center image that is so important to your drum sound. This is especially useful when you’re trying to balance the snare drum in the overheads, which is a common occurrence. Once you compensate for the snare, the rest of the image usually falls right into place.
MIKE MAJOR is a mixer/producer/recording engineer from Madeira Beach, FL. He has mixed and/or produced records for At The Drive-in, Coheed and Cambria, Sparta, As Tall as Lions, Davenport Cabinet, Quiet Company and hundreds of other bands over his 26+-year career. He recently wrote the book Recording Drums: The Complete Guide (excerpted for this blog post), available through Amazon, Barnes and Noble, Guitar Center and most online book retailers.
You can hear some of Mike’s work and connect with him via his website:
www.mikemajormix.com or connect via Facebook or Twitter