Study Hall
Sponsored by
Audio Technica

Church Sound: Effective Microphone Strategies For Choirs

Where should the mics go, and how many are needed in each situation?

By Bruce Bartlett April 24, 2019

One of the biggest challenges in church sound is miking the choir. We want to achieve a good balance, a natural sound, and high gain before feedback. Another goal is to make sure that the microphones are invisible! It’s a tough assignment.

What mics work well for the choir? Where should the mics go, and how many are needed in each situation? The suggestions that follow should point you in the right direction..

The most popular type of choir mic is a small hanging mic. A few of these tiny microphones can be hung over the choir from the ceiling, from rafters, or on stands. They’re almost invisible when viewed from the congregation.

Choir mics are condenser types with a cardioid or supercardioid polar pattern. These patterns reject feedback yet have a wide enough pickup for good coverage of the singers. Condenser mics can be made much smaller than dynamics of equivalent bass response.

Choir mics are built in three parts: mic head, cable, and power module. The mic head puts out an unbalanced, medium impedance signal which travels through the long cable.

At the far end of the cable is a power module with an XLR connector or a terminal block. The module accepts phantom power and sends DC to an FET near the condenser mic capsule. Also, the module equalizes the mic signal and converts it to low-Z balanced.

In some choir mics, the power module takes the form of a flat plate that is mounted in the ceiling. In other mics, the module is a tube with an XLR-type connector.

Mic Placement for Sound Reinforcement

An example of a miniature choir mic.

When placing mics to pick up the choir, a critical factor is gain before feedback. To get enough gain, you must to mic the choir much closer than you would for recording.

Place the mics about 18 inches in front of the first row of singers, and about 18 inches above the head height of the back row (Figure 1).

The mics are raised to prevent overly loud pickup of the front row, relative to the back row. The rows are equidistant from the raised mics, giving a well-balanced sound.

To achieve uniform coverage, use one microphone in the center of every 20-foot span of singers. A choir of 30 to 45 voices should need only two or three mics. Given a fixed micing distance, you’ll get less feedback with fewer microphones. You might want to mount the choir mics on tall boom stands to experiment with placement during choir rehearsals. Once this is done, hang the mics permanently.

In miking a choir, it might seem important to consider the 3:1 rule. When multiple mics are mixed to the same channel, the distance between mics should be at least three times the mic-to-source distance. This prevents phase interference between mics (comb filtering), which is a series of peaks and dips in the frequency response – a colored, hollow sound.

Figure 1: Typical choir mic placement

The 3:1 rule cannot be applied to micing a choir with a few mics. Why? Most of the singers are somewhere between the mics, and those singers will be picked up with some phase interference.

However, since each singer is in a different position relative to the mics, each singer is heard with a different coloration. The effect averages out over all the singers and so is not very audible.

Once the mics are placed, you need a way to hold them in position. Mic cables can lose their orientation as the mic cable uncoils over time, or the mics can swing back and forth in a breeze.


Read the rest of this post

1
2
3


About Bruce

Bruce Bartlett
Bruce Bartlett

Recording Engineer
   
AES and SynAudCon member Bruce Bartlett is a recording engineer, audio journalist, and microphone engineer. His latest books are Practical Recording Techniques and Recording Music On Location.
http://www.bartlettaudio.com

Comments

Have something to say about this PSW content? Leave a comment!

Scroll past the ”Post Comment” button below to view any existing comments. Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Phillip says

This is along the lines of the info that I'm looking for, so far it's been the most informative, but still it'd be fantastic to see more actual examples of how a hanging mic is installed, I see tons of products but not a single company has an example of an installation that I could find.

My situation is a bit out of the topic as it's not for a church; I need to suspend a microphone from a drop ceiling without going into the drop ceiling (against our rules to allow me to do that, unfortunately). This is for gathering questions from the press for press conferences, as a constant complaint is that people cannot hear questions asked. This is in a medium-sized room, coverage area isn't very large (10x10 or so), so I'm trying to figure out how to mount a shotgun from the ceiling (we currently use a boom stand but it looks tacky sticking out the side).

So these hanging mics look like the answer, as I can get hooks that clip to the ceiling tile grid, however what stops them from spinning around if you're just dangling them from the (most seem to come with) thin XLR cable? What about like A/C and general air movement, aren't these so light they'll get blown around? Is there some sort of special mounting hardware I'm missing from the picture?

I'm looking at the Sennheiser ME36 Ceiling Mount Package.

Tagged with:

Subscribe to Live Sound International

Subscribe to Live Sound International magazine. Stay up-to-date, get the latest pro audio news, products and resources each month with Live Sound.