Everyone listening all at once. The Behringer HA400 offers flexible amplification for up to 4 headphones. Whether youre tracking a full band playing to a backing track or just listening to your mix this compact amp gives every performer diverse volume control. Hear everything with clarity. The HA400 promises high audio quality with zero interference no matter what headphones you use. Behringer are relied upon by professional musicians everywhere. With the HA400 headphone amplifier youll become a part of 50+ years of innovation and expertise.