How to Amplify the Sound of Your Choir
Choir Sound Reinforcement
by Vic Hooper
Choir sound is different. Sound technicians are very knowledgeable about microphones, amplifiers, equalizers, sound waves and mic patterns. They work, for the most part, with rock bands, soloists and/or vocal jazz singers and have perfected excellent sound capturing techniques that enhance and bring out the best of such groups. Working with choir sound, however, is quit different. Singers in a choir create an ambient sound that is the result of and is greater than the single voices from which it is made - a synergy of sound if you will. When amplifying a choir, it is this synergy of sound that needs to be captured - not individual voices or sections of voices. The result is what is generally referred to as "choir sound reinforcement".
Finding the best way to amplify your choir to reflect their true sound is a major challenge. After years of working with audio professionals, and doing my own research I have come up with a rather simple solution:
Use a stereo condenser microphone (one will easily cover a 40 voice choir). Such a microphone looks like a single microphone but actually has 2 separate mics within a single container. This provides you with three things:
two microphones with a perfect XY pattern (some professionals argue that XY is not the best, however, it is an excellent choice)
a clean visual - just one mic stand or hanging the mic is even better
a true representation of the sound that is being produced by the choir
Placement of the stereo microphone will depend on the venue and how much resonant/acoustical sound is coming from the “stage”. The most desired position occurs when the microphone is behind and above the director’s head. However, this may not result in the best sound in every case. You will have to experiment and judge the distance from the choir where the mic "hears"/picks-up the choir best. I have used this method in gyms and theatres, venues with good and bad acoustics, large and small rooms to great success.
For larger choirs and/or for outdoor amplification, in addition to the stereo microphone in the centre, you may need a couple of (mono) condenser microphones - one on the left and one on the right about 6-8 feet from centre. This arrangement also works well for recording your choir but that is another article.
Piano and accompaniment
In most cases the piano should not have a separate microphone. The reason is that due to the much closer distance from the microphone to the piano than the microphone to the choir, the signal from the piano will be much greater than the signal from the choir. Even when the piano’s volume is set lower than the choir’s volume, the piano will tend to have a greater presence than the choir. The choir microphone will easily be able to “hear” the piano and pick it up along with the choir resulting in a much more pleasing balance. If the piano is electric or needs to be amplified, point the piano monitor/speaker towards the choir so that the singers can hear it and let the choir microphones pick it up along with the choir. For the same reasons as mentioned for not using a separate microphone for the piano, do not put the line from the piano directly into the main speakers.
Although I do not even pretend to be an expert in sound amplification, I do know that this method is easy to set up and works like a charm!
Here are a couple of stereo microphones I recommend:
Updated: April 2014
Audio-Technica AT2022 (around $300) (I have not used this one. It appears to be for recording devices but I hope it works with sound systems as well. The price is reasonable and Audio Technica produces great microphones.)
Rode NT4 Stereo Condenser Microphone (around $550)
Microphone positioning: Ensemble vocals / Choir (from Shure)
The above diagrams are for mono microphones. When using one stereo mic, you just need to pay attention to the centre position. If using auxiliary mono mics, I would use the diagram to calculate the distance each mono mic should be from the stereo mic. – Vic
Vic Hooper has had many years of experience setting up amplification systems for choirs - as music coordinator at the St. James-Assiniboia School Division, as conductor of Assiniboine Show Choir of Sweet Adelines International and Rainbow Harmony Project.