The Mackie HM-400 is a rack-mountable, 4-channel headphone amplifier designed to provide versatile headphone amplification for artists, musicians, and engineers monitoring through headphones in live stage applications and home, project, commercial, and mobile-recording studios. It features a stereo main output via XLR and 1/4″ jacks and twelve 1/4″ TRS stereo headphone outputs—three per channel—fed by a customizable blend of inputs.
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