Nothing beats the sound of a good, well balanced choir. But recording and/or amplifying a large choir can be quite a challenge, particularly in a reverberant hall or chapel. The most important factor, next to having a well balanced choir, is the selection and placement of microphones. Here we give you some professional guidance about how to mike up your choir for both recording and live sound reinforcement.
Start with a condenser mic.
Without exception you should use a condenser mic for choral groups. Dynamic mics are fine for individual vocalists (used very close, typically hand held) but their frequency response and proximity effects (ie tonal changes with distance) generally produce poor results for choir.
An important requirement for a choir mic is a slight rise in the mid-high frequencies to compensate for the loss of higher frequencies over distance.
For live recording (ie with an audience) it is recommended to use cardioid condenser mics. If recording in a studio, or without an audience, then omni-directional condenser mics may be used. Cardioid mics are uni-directional and reject sound coming from the rear of the mic. Omni mics pick up equally from all directions.
For stereo recording, using 2 omni mics will give you a blended rather than defined stereo image, but lower frequencies are improved. Using 2 cardioid mics, or a stereo mic (has 2 cardioid capsules in one mic) will give you greater control of the stereo or positional image.
For live sound reinforcement (PA)
Only cardioid or super-cardioid condenser mics are appropriate for live PA to minimise the risk of feedback. Super-cardioid mics (or shotguns) have a narrower pickup angle and are often used when you are unable to get as close as you would like. When used closer to a choir they can help to strengthen a soloist or small section, but should be used sparingly.
For fixed PA installations, especially chapels or stage productions hanging choir mics are particularly convenient. An example is pictured at left (Audio Technica U853R) . These mics are very small with an angling wire or bracket and are near invisible to the audience.
Placement for recording
In general, recording requires distant miking so that you pick up the natural ambience of the choir and the room. If the room is relatively dead you may need to add some reverberation during the recording process. Two mics are sufficient for stereo recording.
Start by placing the mics about 3 to 4 metres in FRONT of the choir and about 0.5 to 1m ABOVE the heads of the back row. ALWAYS use two identical mics or a single stereo mic. Position cardioid mics at the centre of the choir (in front) and about 1m apart.
Alternatively, for single point stereo miking, place the mics with their front edges touching at an angle of 110° to each other (similar to a single stereo cardioid mic).
Before finalizing the position listen to the sound through the mixer with headphones or monitor speakers (if you are in a control room). If there is not enough ambience (assume the room isn’t “dead”) and the choir seems too close then move the mics further from the choir. On the other hand, if the choir is lost or too distant then move the mics a little closer.
Once you have the distance right you can also hang the mics if convenient and run a fishing line across the stage and around each mic to aim them correctly. This is useful if you have an audience and prefer not to have stands visible.
Placement for PA use
For live sound reinforcement it is important NOT to pickup the room ambience or sound from the PA speakers. This means you MUST place the mics closer to the choir.
For closer miking you should use one mic placed in the centre of each 4 to 6 metre span of choir. Only 2 cardioid mics should be needed for a choir of up to about 45 voices. Above that you may need additional mics, but lean toward less rather than more as every mic adds to the complexity of the sound and increases the risk of feedback.
A recommended microphone for most live situations is the Rode M3 cardioid condenser mic.
Place each mic about 0.5 metre in FRONT of the choir and about 0.5 metre ABOVE the heads of the back row. Aim them toward the back row then adjust as necessary to balance volume with the front (closer) voices.
If you are unable to place mics as close as you would like then you can use fixed super-cardioid mics (shotguns) typically mounted behind a proscenium or hung from an overhead bar. Again, the fewer the better and aim them as if they were placed on closer stands.
Stage monitors can be a major problem when miking a choir as they can feed back into the choir mics. The best option is to use only the FOH (Front Of House) speakers for the choir voices and use the monitors for accompaniment music only (if required by the choir).
If choir members have difficulty hearing themselves, then turn down everything else on stage. Start by singing a capella if necessary then bring up the accompaniment to give sufficient balance. It is better to increase the choir level in the FOH speakers than to send the voices back through the monitors.