How to record a 50-strong choir and piano accompaniment with just five mics
Question from an Audio Masterclass visitor... "How would you suggest I go about recording a male/female pops choir of about fifty people, with grand piano accompaniment? I'm working with a Digi 003 and Presonus 8 ch. preamp in a portable rig. I have three large- and two small-diaphragm condensers."
Let's assume that the choir and piano sound great in the auditorium where they will be recorded. If they don't, then you'll probably want to let someone else have the gig.
But if they do sound great, then all you have to do is capture that greatness, and it really won't be difficult.
Firstly the choir. There are fifty people in the choir, but this doesn't mean you need fifty mics. Two will do. Three may be better. There shouldn't be any reason to need more. More mics generally lead to a more cluttered sound.
You could, for instance, opt for the coincident crossed pair technique, where two microphones are positioned very close together, one pointing left and the other pointing right.
For this to work properly, the choir needs to be arranged into an arc of a circle around the mics. A 120-degree arc will be good. The mics should be at the center of the circle so that all members of the choir are roughly the same distance from the mics.
But suppose that the choirmaster doesn't like this idea and wants the choir in straight rows. Now the ends of the rows will be more distant from the mics, and therefore won't be picked up as well.
Instead of the crossed pair, you can use spaced microphones. One mic should be a quarter of the way from the left, the other quarter of the way from the right.
This will pick up a rich, spacious sound. You might prefer it to the coincident crossed pair.
The only drawback to the spaced technique is that when you play the recording back it may sound half in the left speaker, half in the right, with nothing in-between.
Since the whole point of stereo is to create a full 'sound stage' that goes all the way from left to right, clearly this is not appropriate.
However, if you put a third mic in the center, you can fill the 'hole in the middle'. You won't need as much level from this mic - just bring it up as far as you need to fill the hole.
Whichever technique you choose, clearly it is best if the mics are the same. But if they are not, don't let that hold you back. You can match up the sounds with a little level and EQ adjustment. It is unlikely that anyone other than another sound engineer will be able to tell.
As for the piano, one way of recording the piano is to place the mics on stands that are just a little higher than the casing. The mics don't have to 'see' the strings. The audience hears the sound reflected from the lid so there is a good argument that the mics should too.
Place the mics about 60 cm (2 feet) apart about 60 cm from the instrument down at the end away from the keyboard. This will give you a full rich sound that is a good starting point for experiment.
If the choirmaster insists on having the lid of the piano closed, then you have a problem. Tell him that the recording will be terrible and insist on at least using the short stick to prop up the lid.
One nicety is that the piano mics should point away from the choir. This will give you more control in mixing. This will depend on the orientation of the piano, and you might choose to compromise the ideal position for sound quality so that you can gain more control.
And that's it! How to record a choir and piano with just five mics.
Will you send in the recording and let us all hear it?