A recent post on feedback prevention prompted a good question from Ryan, a reader.
“…there was one phrase that jumped out at me. Specifically, ‘Regarding floor monitors, vocalists should be very close to their floor monitor.’ I wanted to ask what the reasoning is behind this? I would think the further away the singer is, the more the sound is diffused; ergo, feedback is reduced.”
One of the hard parts of live audio production is taking into account all the different factors that are needed and finding the balance in using them all to create the best sound.
Monitor usage is a perfect example. A musician needs monitors for hearing sounds to be in key and in time.
The sound tech needs the musician to sing into a microphone using the right technique so they can get a solid sound for mixing. The audience/congregation needs to hear a great house sound.
Looking specifically at a fictional vocal singer, we have five factors to take into account to make all of this work:
—The microphone they use
—How they use the microphone
—The monitor they use
—How they use the monitor
—What they hear in the monitor
1) The microphone they use
Microphones come in a variety of types with a variety of frequency responses but you need to focus on their polar pattern for now.
The polar pattern is the area around the microphone head and how a particular microphone picks up sound around it.
A cardioid pattern, which picks up primarily in the frontal section with reduced pickup on the sides. (click to enlarge)
For example, an omnidirectional polar pattern picks up sound all around the microphone. A cardioid picks up sound in the front and sides but not behind the microphone.
Let’s give the vocalist a common, albeit aging, Shure SM58 microphone. This is a dynamic vocal microphone with a cardioid polar pattern.
As an aside, you need to find out the polar pattern of your microphones. They will either have a small picture of it on the microphone or you can check out the manuals.
Most microphone specs are available online so don’t fret if you don’t have the manuals.