PreSonus HP4

4 screaming-loud (130 mW per channel) stereo headphone amps. Wide dynamic range. Can serve as control room monitor control w/ level control & Monitor Mute button. Daisy-chain multiple units via 2 balanced ¼” monitor outputs. Compact 1/3U rack-mount chassis. Mono summing switch. 2 balanced ¼” line inputs. Super-quiet with -98dB noise floor. Headphone level control