Most of the Voice Box’s modes require both an instrument and microphone to be connected to work properly. For example, in the photos you have the Voice Box set to Vocoder; Vocoder mode will not make any sound unless an instrument or sound source is plugged into the INST input jack and a microhpone is plugged into the XLR input MIC IN. Then to hear the vocoder effect, you must speak into the microphone while the instrument sound source is producing a signal.

Based on the photos and your description it sounds like you have only tried either the MIC IN or the INST in but not both together?

On the Voice Box there are two modes where you can just plug in the microphone and hear an effect: OCTAVES and UNISON+WHISTLE modes. You can test the microphone to see if it is working properly through the Voice Box by setting it to either of these modes and speaking through the microphone.

If you are looking for Vocoder effects that do not require an instrument as well, check out our V256. With the V256 you can plug in a mic and create vocoder effects without the need for an instrument.

Can you try taking the Voice Box out of the signal path just to make sure the microphone signal is making it through the cables to the computer? So disconnect the two XLR plugs currently inserted into the Voice Box and connect these XLR plugs together, the mic signal should now be going straight into the computer.

Also one other note: make sure the LED near the MIC BYPASS footswitch is lit to hear the Voice Box effects. Press the MIC BYPASS footswitch to toggle between effect mode and bypass mode.

Do you hear any sound from the microphone when plugged into the Voice Box? Try toggling the MIC BYPASS footswitch, do you hear any sound when the Bypass LED is off?

If the LED near the MIC BYPASS footswitch goes on and off each time you press the footswitch, then the footswitch is doing its job.

I’m not sure what’s going here. Even if you don’t hear microphone in effect mode it should be audible while in Bypass.

Can you send me the make and model of the headphones?

Which switch do you suspect is bad?

The user manual for the headphones doesn’t provide too much info. Most likely the problem is that the microphone signal from the headphones is unbalanced but the Voice Box requires a balanced microphone signal into the MIC IN connector. Does your mixer have a balanced send or output of any sort? If it does try plugging the mic into the mixer and then sending its signal on a balanced connection to the Voice Box.

It sounds like the V256 would be a better fit for you but it shares the same mic-pre and XLR output driver circuitry from the Voice Box so if you can’t get the mic working on the Voice Box then it probably won’t work for you on the V256 either.

Try the following setup:
1. Ensure the LED near the MIC BYPASS footswitch is lit up. This LED toggles on/off each time you press the MIC BYPASS footswitch.
2. Turn the BLEND knob up, or clockwise, to its maximum setting. Doing this ensures that you only hear the vocal effect and not your original vocal.
3. Turn the MODE knob until the LED next to OCTAVES is lit.
4. Turn the VOICE MIX knob fully clockwise so that the effect raises your vocal pitch by one octave.
5. Talk or sing into the microphone, you should now hear the high pitched up octave effect.
6. If you do, turn the HARMONY REVERB knob up to its maximum position, now you should hear reverb on the up octave effect.

Let me know if this works.