What is a stage-floor microphone?
It is a microphone placed on the floor of a theater stage, usually near the front edge, to pick up actors. It is also called an "area mic" because it picks up over a broad area, as opposed to a headworn wireless mic which picks up only one actor. It's also called a "foot mic" because it is placed near the footlights, or is called a "safety mic" because it provides a backup in case an actor's wireless mic fails.

Does the TM-125 require phantom power?
Yes, 12 to 48 volts. That is supplied by most mixers. The mic simply plugs into the mixer mic input to receive power. If your mixer does not have phantom power, you need to get a phantom power supply such as the ART Phantom III. Plug the mic into the phantom supply, and connect the supply output to your mixer mic input.

How many mics do I need? Where should I place them?
20’ stage: 1 mic center stage.
25-30’ stage: 2 mics 12 to 15 feet apart.
35-40’ stage: 3 mics 15 feet apart.
45-50’ stage: 3 mics 17 feet apart.

The FRONT of the mic is indicated by an arrow on the bottom of the mic. As you face the stage from the audience, the cable should exit to the left out of the mic. The long dimension of the mic should be parallel with the stage edge.

Can we use one TM-125 on a 24-foot stage? Would we have noticeable pick-up loss on the fringes of the stage? Would two mics be better?
I'd recommend two mics about 12 feet apart to cover a 24-foot stage. They would pick up actors at the ends of the stage with nearly the same loudness as actors at center stage. In contrast, a single mic would pick up actors at the ends of the stage about half as loud (-6 to -7 dB) as actors at center stage.

Try to turn up only the mic nearest the actor speaking, so that only one mic is turned up fully at a time. You'll get a clearer sound and more gain before feedback than if both mics were on all the time. If two actors are on opposite sides of the stage, turn up both mics.

How do I get the mic signals to my mixer? The supplied mic cables don't reach to my mixer.
Purchase some mic extension cables (microphone cables) and plug them into the mic connectors. Nady offers some good quality, low-cost cables at amazon.com. Another option is a microphone snake (www.whirlwind.com, www.hosa.com, www.procosound.com).

Does the mic pick up sound only along the floor?
The mic picks up best at 30 degrees above the floor, where the actors' mouths are on the average. It is about 7 dB less sensitive straight overhead (90 degrees), and has maximum sound rejection at 155 degrees away from the front. So to reduce feedback, the house speakers should be toward the backside of the mic.

Is the TM-125 a replacement for wireless lavalier mics?
While the TM-125 has less gain-before-feedback than wireless mics, many users report that the gain of the TM-125 is adequate. The TM-125 is less hassle to use than wireless mics, and costs less. For example, school children in a play might accidentally shut off wireless mics, break them, or put them in the wrong place. Many schools do not have the budget for wireless mics, and they appreciate the lower cost and problem-free operation of the TM-125.

Can I reduce footstep noises by putting the mic on a foam block or other padding?
No. The mic diaphragm is perpendicular to the stage floor, so floor vibrations produce no audible signal from the microphone. The mic will pick up foot steps acoustically, the same as your ears. If you pick up the mic off the floor while reinforcing footsteps, you should hear no difference in the loudness of the footsteps. You might ask the wardrobe people to put rubber or felt soles on the actors' shoes (unless felt is too slippery). Or carpet the stage floor.

It helps to brace the stage more thoroughly from underneath so that it doesn't creak. You might also apply some sound damping material such as Fatmat eXtreme at www.fatmat.com.

Some people mount the mic on a 2-foot square sheet of Plexiglas or Lexan, and tilt the sheet upward about 10 or 20 degrees so that the mic does not "see" the feet. This can produce a coloration in the sound, however.

How can I maximize gain-before-feedback?
See the suggestions on page 2 of the TM-125 datasheet, and click here to download our free article, "10 Tips to Reduce Feedback". Also, place the mics as close to the actors as possible without getting in their way. This has three benefits:
1. The mics receive a higher SPL, which increases gain before feedback.
2. The mics are farther behind the house speakers, which increases gain before feedback.
3. The mics are farther from the pit orchestra, so they pick up less orchestra.

Use a line array or column speaker overhead. It projects much less sound onto the stage than a conventional speaker.

Mount the speakers closer to the audience and farther from the mics.

Try the A-B loudspeaker scheme: Assign each mic to a separate output bus, with each bus feeding its own power-amp channel and loudspeaker. That effectively creates 2 to 4 independent PA systems, one per mic. That practice minimizes the number of open mics per PA system, which reduces feedback. The speakers are mounted close together so that the reproduced actor's voice does not shift its position noticeably when the actor walks from left to right. This system also reduces phase interference (comb filtering) when two or more mics are on at the same time.

In what situations are boundary mics NOT recommended?
(1) When the venue is very live and full of hard surfaces. (2) When the distance from the mics to the speakers is less than the distance from the speakers to the audience. Overhead clusters tend to result in marginal gain-before-feedback unless they are line arrays or column speakers.

Can your mics be used for an "assisted listening" setup for our hard-of-hearing patrons?
Yes, the TM-125 or TM-125C microphones work quite well for that purpose. The actors' volume as picked up by floor mics tends to be very consistent. Also, earphones sound clearer than loudspeakers because the earphones eliminate the room acoustics.

Can I paint the microphone?
Yes, just be very careful not to paint the front and back foam windscreens inside the grille. Follow this procedure:
1. Cover the grille holes with masking tape to keep paint off the foam windscreens.
2. Spray paint the mic.
3. When dry, remove the masking tape from the grille holes.
4. Hand-paint the grill holes -- do not spray-paint.

How are your mics tested?
We 100% test our mics for frequency response, off-axis attenuation and sensitivity using Time Delay Spectrometry (TDS) and a TEF analyzer. With TDS or TEF measurements, a loudspeaker generates a frequency sweep from 20 Hz to 20 kHz. The microphone under test picks up that sweep. The mic's signal is run through a bandpass filter that tracks the sweep, and filters out sound reflections from the room because they are at a different frequency than the tracking filter.

As an example, suppose the loudspeaker is sweeping from 500 Hz to 1000 Hz. First, a 500 Hz tone reaches the mic and goes through a bandpass filter centered at 500 Hz. That 500 Hz tone also travels to the room surfaces and reflects back to the microphone after a propagation delay. By the time that 500 Hz reflection reaches the mic, the sweep (and the tracking bandpass filter) have already reached 1000 Hz. So the bandpass filter removes that 500 Hz reflection from the measurement. As a result, an anechoic measurement can be made in an ordinary room.

Where do you sell your microphones?
We sell directly from this web site, and also from our sole UK distributor, 10 Out of 10 Productions Ltd. Please purchase our mics from them if you live in the UK.

To order from our web site, click here:    

Can you take purchase orders?
Yes. Please click on the "Place An Order" button above for details.

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