The Superlux HA3D is a portable, stereo headphone amplifier designed for demanding and critical audio monitoring. This audiophile-quality headphone amp is ideal for adding headphone feeds for portable, studio and audio enthusiast applications. The HA3D provides 3 independent headphone feeds from balanced or unbalanced line sources. Each headphone output is controlled by the associated level control, equipped with independent peak LED, and 1/4-inch output connector. With its extended bandwidth and high current/voltage drive capability the HA3D can drive headphones of various impedances to high levels with very low distortion; important for monitoring in high SPL environments. It can be powered from two-AA batteries or an external DC supply. The HA3D provides 3 independent headphone feeds from balanced or unbalanced line sources. Each headphone output is controlled by the associated level control, equipped with independent peak LED, and 1/4-inch output connector. With its extended bandwidth and high current/voltage drive capability the HA3D can drive headphones of various impedances to high levels with very low distortion; important for monitoring in high SPL environments. It can be powered from two-AA batteries or an optional external DC supply.