The Sonifex RB-HD2 Headphone Amplifier is a high performance 2-way stereo headphone distribution amplifier for driving up to 2 pairs of professional stereo headphones from a single stereo or mono input. A switch on the rear panel enables the distribution of a mono signal to all four outputs (i.e. both earpieces of a pair of stereo headphones) via the left channel input. The stereo/mono switch is located on the rear panel to prevent accidental knocking.
 
The XLR-3 inputs are electronically balanced and can be wired unbalanced. There are two pre-set controls on the rear panel that adjust the level of the master input signal to the outputs. Each output is on a ¼” stereo jack socket and is designed to drive 150mW into 32 ohm to 600 ohm stereo headphones. The outputs are individually buffered with their own front panel volume control. A LED power indicator on the front panel displays the power supply connection.