It depends upon the product. Most floor mics that that are specifically designed for that application (like the Crown/AKG PCC160) are robust enough to handle someone stepping on them occasionally, so the make / model is important to know. Other mics may be more fragile.
Placing a sound reflector like a footlight shield behind the microphone may make the mic more visible to the performers, but could have a bad effect on the sound delivered by the microphone due to sound reflections from the shield coming back to the microphone slightly delayed (which is the entire advantage that a floor mic has in that there are no oddly timed reflections from surrounding surfaces coming to the microphone element to mix withe the original sound. If you chose to try to 'flag' the presence of the microphone to the performers, then use a perforated material, and install some high-density (5-7 pounds per cubic foot) fiberglass between the shield and the microphone. Ductliner board that you can buy at an HVAC contractor satisfies this requirement and is easy to cut into shapes.
Setting them on a 1/8" thick felt pad can also protect the floor from scratches, as well as add some vibration isolation from foot-fall noises. The best way to reduce foot-fall noise is to make sure that the performers are wearing rubber soled shoes, not leather soled shoes. It also helps to do some movement training so the performers aren't 'tromping' around, but instead walking like a ninja.
Also to be considered is the relative location of the performers to the microphones. Most floor mics have a vertical sensitive area of about 60 degrees up from the floor; so if you get too close to them, then they actually pick-up less sound because the performer's mouth is too high relative to the distance between their shoes and the mic. A good rule of thumb is to do your blocking so the performers are no closer to the microphone than they are tall. This also creates a buffer zone for mis-steps (they would have to make two steps to even reach the mic). This is good practice anyway, as this is the same buffer zone you want for performer safety so no-one accidentally steps off of the edge of the stage and falls into the audience or orchestra pit.
Another thing to consider in the performer's blocking is that if the performer can't see the floor mic, then the floor mic can't hear the performer. There needs to be a clear line of sight between the performer's mouth and the microphone. It can't be blocked by scenery, furniture, or other actors.
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Erich Friend
Theatre Consultant
Teqniqal Systems LLC
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Original Message:
Sent: 11-03-2023 10:56
From: Michael Johnson
Subject: Stepping on Floor Mics
Dear Folks
Am wondering if anyone has come up with a good way to protect floor mics. I am thinking of creating a sort of "footlights" sheild to place behind them. Other solutions?
Thanks for your thoughts
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Michael Johnson
Teacher
Trinity High School
NC
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