CAD Audio HA4 4-Channel Stereo Headphone Amplifier
The HA4 is a compact stereo 4-channel headphone amplifier.  This rock-solid amplifier features four discrete channels with individual volume controls. The HA4 has exceptional signal-to-noise ratio to provide the listener with amazing clarity. This product is an essential tool for enhanced listening performance and a vital accessory for the recording musician.  Its small size makes it easy to transport to the studio.