The PreSonus HP60 is the most flexible and advanced headphone mixing system available for professional and project recording studios as well as live sound in-ear monitoring systems. Loaded with six independent, loud and clear headphone amplifiers, the HP60 features dual stereo inputs as well as external input, for each channel allowing you to mix between three stereo audio streams (mix A, mix B, and external input). Stereo output is also available on each channel to send line level headphone cha..