Professional 4-channel headphone amplifier that allows up to four people to listen to a recorded take at the same time, while being able to adjust their own individual headphone volume It is also great to use during playing or recording, allowing listeners to hear the main mix and providing high quality sound even at full volume. It is equipped with 6.3mm TRS stereo input/output and comes supplied with a 12-18V DC adapter. Max. output level: +22 dB. Signal to noise ratio: >98 dB. Output impedance: minimum 100 Ohm each channel. Max gain: 20 dB per channel.