All headphones are not the same. Each model has its own character, its own sonic signature. That’s why we’ve created a headphone amp that lets you choose from four different output impedances (two outputs each of 0.1, 33, 82 and 120 ohms) to experience a sound that best suits you and your headphones.<br><br>The AT-HA5050H is a hybrid Hi-Res Audio headphone amplifier – hybrid because it employs a pair of tubes at the preamp stage and transistors at the power amp stage. Having tubes in the preamp adds warmth and depth to the music, while the bipolar transistors provide distortion-free Class A amplification that is powerful enough to drive headphones of varying impedances without any problem. To further optimize power supply in the amplifier, each part of the amplifier is fed by individual power supply units with fast recovery diodes and regulating circuitry.<br><br>The AT-HA5050H is equipped with two analog inputs (L/R RCA line jacks and L/R balanced XLR jacks) and two digital inputs (S/PDIF digital coaxial input and USB input with selectable Asynchronous and Adaptive modes). The state-of-the-art DAC is optimized to be compatible with digital audio formats up to PCM 32-bit/384kHz and DSD128. Additional features include classic analog VU meters with VU range selector switch, large volume control knob, and an input attenuator switch.