88 Keys and a Microphone

A couple decades ago, a Sunday school teacher at my church decide she wanted her first and second graders to perform in the “big church”.

So, five volunteers carried a vintage Kimball piano into the main sanctuary and placed it in front of the platform. We had one rehearsal where I simply opened the top of the upright and positioned a Shure SM 57 microphone (on a mic stand) slightly inside at the middle of the harp. To my surprise and joy, it sounded pretty authentic.

At the actual event, I switched the 57 for a SM 58 and had an even better result. This single event spurred me on my journey to become an expert at micing acoustic pianos.

A piano reproduces frequencies from 27.5 Hz to over 4 kHz. That is a very wide range and it is spread out over the size of the piano. An upright piano has one size harp, a baby grand has another size and a grand piano another. That said, I use one technique for uprights and another for grand pianos.

So, let’s look at the techniques I use to capture all those frequencies.

I know that you (as a volunteer) will be limited to the microphones your church has (plus any that you happen to own). I’ll tell you what mics I currently use for pianos at the end of this post. For now, on with my story.

Once I had used one microphone successfully on that old Kimball upright, I figured two or three mics would sound even better. Currently I use two microphones on uprights. I set one toward the bass side of the harp and one toward the treble side. Using condenser mics, I set them about 24 inches apart. If I am mixing in a true stereo system I will set the mixing console channel pan to 9 o’clock for the bass and 3 o’clock for the treble. Even in a mono system the two mics are the way to go.

I also want to capture the “attack” of the notes but not the mechanical sound of the hammers hitting the harp strings. So, I position the mics 8 to 10 inches from the hammers. I have been using this technique for the last fifteen years with great success.

In certain situations, however, I will position an additional microphone at the center of the sound board at the back of the piano. Placing a mic about 8 inches from the sound board adds a little more warmth and authenticity to the sound of the piano. I only use this technique when there are very few instruments being played on the platform, as I want to avoid sound bleeding into this microphone.

That’s it on how I do it—you can use these exact techniques or experiment with your own. Maybe try three mics on the harp and two on the sound board., or whatever you want. Think of my techniques as a possible starting point.

With grand pianos I also use two condenser mics. I open the top of the piano and set up one microphone on the bass side of the harp and one on the treble side. The mics should be about ten inches above the hammers and about 24 inches apart. This technique is very much like the upright piano mic placement with comparable results. Just like with an upright piano the goal is to capture an authentic piano sound and this two mic method seems to work quite well.

In certain situations, I add another mic under the grand piano below the sound board. I will set a large diaphragm mic 8 to 10 inches from the sound board at about the center of the piano. I learned this technique when mixing a Burt Bacharach concert at the Beverly Wilshire hotel in Los Angeles. I set up my microphones the way I usually do for a grand when Burt’s tech told me he wanted a large diaphragm mic under the piano. At the time, the only large diaphragm mic I had was an Audix D6 kick drum mic. I was surprised how good the mic sounded when combined with my two condensers microphones.

That show was about twelve years ago and I have since incorporated the technique of also micing the sound board into my bag of tricks. Of course, when I can I mix my pianos in stereo but this technique works in either mono or stereo.

Now, getting the mics I currently use... Over the years I have settled on AKG C1000 condenser microphones for pianos. I like using the super-cardioid pattern when miking pianos. As for the sound board, my choice is the Sennheiser MD421. I realize that there are a lot of microphones out there that you can use. I also realize that you are limited to the mics your house of worship has in its arsenal (plus your own).

On the other hand, I have had the opportunity to use and test dozens of different microphones and there is no doubt that great microphones make great audio easier. That doesn’t mean you can’t get good result with the mics you have. One thing you should do when using multiple microphones on your piano is listen to the mics individually. Bring up the bass side microphone up by itself. Then bring up the treble side by itself. Once you have what you think is an accurate sound from each mic, blend them together in the mix.

If you are using one or more sound board mics, do the same thing. Again when you are satisfied with each individual microphone, blend them together. Good luck.