Mackie HM-4 4-Channel Headphone Amplifier

The Mackie HM-4 is a compact 4-channel headphone amplifier designed for studios, rehearsal spaces, and home recording setups where multiple listeners need to monitor a single stereo source. It accepts one 1/4" stereo input and distributes the signal to four 1/4" headphone outputs, each equipped with its own level control knob. This allows each listener to adjust their monitoring volume independently without affecting anyone else in the group.

Built with Mackie's signature rugged metal construction, the HM-4 is designed to hold up in busy studio environments. Its ultra-compact form factor — measuring just 4.3 x 2.3 x 2 inches — means it takes up minimal desk or rack space. Power is supplied by the included 12V AC adapter, keeping the unit simple and ready to use out of the box. Whether you're running a recording session with multiple musicians, collaborating on a mix, or simply sharing audio with others, the HM-4 provides a clean and reliable headphone distribution solution.