Sara Chambers from Alaska emails with a question:
“Hello! Thank you for your good work! I appreciated the article “Ask the Expert – mic recommendations for groups of singers” . However, the choral mic’ing solution didn’t address a “deep” choir, where the male voices may be a few tiers higher than the women, and therefore too far from the mic to be heard. (Our choir is about 15 people and sits on three riser levels.)
What choral mic solution would you (or Tim Horton) recommend in that situation? We are currently facing the issue and would love some help.”
Tim Horton, sales engineer at SFL Group replies:
If the choir really is that small – 15 people, three tiers, five people per tier, then the same technique I recommended before applies. A pair of mics at the front in front of the second and fourth people in the rows. The voices will naturally blend together. Let the vocalists do the work, not the mics. You shouldn’t be looking to redress the imbalance of choir levels by mic’ing each section – it’s impossible in the live environment.
Even if it is bigger and it’s 15 people per tier on three tiers (45 total) the technique remains. We do a gig with a choir of 200+ who are spread across 6-8 tiers, 30-odd people wide, and there are 6 mics on the front 3-4 rows, with a further 6 mics in front of the back 3-4 rows. This 200+ choir was just part of a large gospel group, with a (loud) 12-piece band, 8 BVs and lead vocals. The advantage of huge choirs is that you don’t need huge numbers of mics. There’s enough of a critical mass for just a few mics to pickup appropriately.
Related posts:
Is there some rule of thumb that the distance horizontally between the microphones should be at least three times the distance from the microphone to the mouth(s) of the closest singers?
Hi Jeff,
I must confess, I’ve not come across this rule of thumb before. My gut feeling would be; no, it’s not important. For example, how would it work with a crossed pair? This is a very common mic technique but does not adhere to your rule of thumb…?
For me, the critical distance is between mic and choir, come to think of it: between mic and any source. The rule of thumb i work to says: the closer I get my mic to source, the better the gain before feedback ratio. Physics tells us that for every doubling of distance between source and mic, we lose 6dB. You could also view this as a loss of half the effective volume. The difference between 2ft and 4ft is half the volume. On the flip side, 2ft and 1ft is twice as loud. And so on…
As I’ve said in my previous posts, try to get the mics as close as possible to the singers; anything around the 4ft mark is probably pushing your luck – even with the most directional of pickup patterns. Two feet away is probably the ideal, unless you can get closer.
Please don’t just take my word for it though; learn by doing. Get yourself a pair of mics and experiement with different positions; see what you prefer…
I hope this helps?
Happy mic’ing!
The ‘rule’ I was referring to has to do with potential interference when using multiple mics and a sound source is picked up by more than one mic. This interference is minimized by the ’3 to 1 principle’ described on pp. 19-20 of Shure’s Guide for Houses of Worship. Here’s a brief quote from
http://www.shure.com/idc/groups/public/documents/webcontent/us_pro_audiohousesworship_ea.pdf
“The second form of interference is the result of multiple microphone pickup and can occur whenever more than one microphone is used. If the microphones are at unequal distances from the sound source, the sound picked up by the more distant microphone will be delayed relative to the near microphone. When these signals are combined in a mixer, peaks and notches occur at multiple frequencies which are related to the delay time, and hence, to the distances between the microphones. This effect is called “comb filtering” because the resulting frequency response curve resembles the teeth of a comb. As the delay time increases, comb filtering starts at lower frequencies. It is especially noticeable at middle and high frequencies, and creates a “hollow”, distant sound.
The solution to this problem is to use the three- to-one rule: for multiple microphones, the microphone- to-microphone distance should be at least three times the source-to-microphone distance.
For example, when using individual microphones on a vocal group, if a singer’s microphone is one foot away, then the next nearest microphone should be at least three feet away from the first. This insures that direct sound from the singer will not be strong enough to cause noticeable interference when picked up by the more distant microphones. As the source- to-microphone distance increases, the distance to adjacent microphones must also be increased.
An implication of the three-to-one rule is the following:
avoid picking up the same sound source with more than one microphone. Microphones should be placed and aimed to minimize areas of overlapping coverage. This is important for a number of sound applications: for area pickup applications, such as choir lofts and stages, each section or area should be covered by only one microphone; for lectern applications, only one microphone should be used; when a lavalier microphone wearer speaks into a fixed microphone, one of the microphones should be turned down.”