Behringer Microamp Ha400 4-Channel Stereo Headphone Amplifier

4-Channel Distribution: Connects up to four pairs of headphones at the same time. Independent Controls: Four separate volume knobs adjust individual output levels cleanly. High-Power Sections: Utilizes ultra-low-noise 4580 operational amplifiers for excellent sonic performance. Rugged and Compact: Pocket-sized form factor built with a durable, road-ready chassis. Ready to Use: Includes a dedicated 12V DC external power adapter.