Headphones Amp for Pedalboards with AUX-in and XLR out

Headphones Amp for Pedalboards with AUX-in and XLR out
Assisted silent rehearsal.
This device is actually a full stereo mixer with a headphones out. The standard input can be used to connect the signal from your pedalboard (stereo or mono) and the AUX-In can be used to connect a phone/mp3 player/soundcard line out or other similar device. Both inputs are mixed and routed to the headphones out to assist you on a “silent” rehearsal.

It is also equipped with a TRS THRU output, this way whatever signal is routed to the input can also be picked up by any other device you’ll connect to the THRU output (like an amp, or another pedal) and it will remain unaffected because of the very high input impedance of the device’s buffer.
Internally a separate mixer circuit converts the Stereo Input signal to mono and routes it to the balanced XLR output. The input volume control does not affect the level of the XLR out. The AUX-in signal does not output to the XLR.

- ST/M Toggle switch: allows you to select the type of signal (Stereo or Mono) that is being routed to the input. If you are working with a mono signal this toggle switch ensures that you will be hearing the same mono signal in both L+R channels of your headphones.

3 knobs:
- Input Volume knob
- AUX-IN volume knob
- Headphones-out volume knob

If any of the input signals is too hot and causes distortion to your headphones just attenuate it from its respective volume knob. 

Technical specifications:
▹  Input impedance: 10Mohm
▹  THRU output impedance: equal to output impedance of the device you’ve connected to the input.
▹  XLR output impedance: 100ohm
▹  Circuit equipped with filters to avoid RF interference.
▹  Voltage Required: DC 9-12 Volt (12V will offer more headroom).
[Do not exceed recommended voltage! It may damage the circuit.]
▹  Polarity: Center Negative
▹  Typical current draw: 40~200mA (depends on volume setting, and type of headphones)
▹  Typical headphones-out power: 300mW for 32Ω headphones @9V