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.
One stereo main input via XLR and 1/4" jacks can be mixed with a per-channel 1/4" stereo aux input. Each channel offers 2-band EQ for quick tone shaping, stereo balance or main/aux input mix control, and output level adjustments. Also on each channel are switches for muting left and/or right signals and operating in stereo or mono. 7-segment LED meters display main input and per-channel output levels.
The HM-400 ships with an IEC power cable and occupies 1 RU in a standard 19" rack.
- Distribute signal to up to twelve pairs of headphones
- Occupies 1 RU
- One stereo main input via XLR or 1/4" jacks
- One 1/4" stereo aux input per channel
- One stereo main output via XLR or 1/4" jacks
- Three 1/4" headphone outputs—one on the front panel and two on the rear—per channel fed by an output level control
- 2-band EQ per channel for quick treble and bass adjustments
- Per-channel Balance knob allows control of left/right level balance or aux/main input mix
- Switches on each channel for L/R mute and St/2-Ch (stereo/mono) mode
- 7-segment LED metering for input and each output channel
- Heavy-gauge steel chassis for rugged durability