I’ve had the pleasure of working with a few vocal groups recently and have been refining the process of capturing a choir singing along to a backing track. Good monitoring is essential for vocalists to pitch and ideally in the studio we can give everyone headphones, but not many places can cater for a large vocal group unless your budget stretches far enough for a place like this.
For the Vocal Works Gospel Choirs last album (Fourteen), we tracked in the big room at Real World Studios and hired in 50 wireless headphones from Silent Disco, which worked a treat as it gave everyone independent level adjustment, avoiding spill and the cable chaos a wired setup would have caused.
For those moments when you don’t have enough headphones, and it’s not worth hiring in a load of gear, there are still ways to get great results.
In this example for Bath Academy of Musical Theatre, the singers had an instrumental backing that they wanted to record over. We didn’t have the facility to give everyone headphones so the setup I went for was quite simple in the end. I used a pair of AKG C414 mics in Blumlein configuration, placed above a monitor speaker with the choir arranged in a circle around the mics.
Now the room you record in will have a big influence on the sound, we recorded this in a relatively dry and well proportioned room (a modern music department in a local school) which really helps by reducing the amplitude of reflections from the walls. This is particularly important when you are playing the backing track into the room whilst recording as it reduces what I call indirect spill which will add unwanted ambience to the backing track.
Placing the monitor speaker below the mics puts it in the most off-axis position in the Blumlein pickup pattern, so you get attenuated direct sound from the monitor speaker into the mics (though this does not eliminate the playback sound from entering the mics), and the monitor ideally should not have an upwards facing driver. Also, you need to set the monitor volume to the lowest you can get away with for the vocalists to feel happy and pitch well.
In the video example, we recorded the soloists individually afterwards using headphone monitoring, but all the ensemble parts (from 2:22 onwards) were recorded live along with the backing track in the manner described. When it came to mixing, I was impressed at how much easier it was to get the backing track to sound good with the choir. In previous approaches I was never completely happy with how the vocal mics added a room sound to the backing track, especially when you start compressing them.
As a way of quickly and easily tracking a vocal ensemble with minimum hassle, this definitely works. I have also come across similar examples of this used in studio recordings, such as using a figure of 8 pattern mic with singers either side on-axis, and a monitor at 90 degrees in the maximum off-axis position.