Hybrid Headphone Amplifier


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. 

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/384 kHz and DSD128. Additional features include classic analog VU meters with VU range selector switch, large volume control knob, and an input attenuator switch. 


    • Two E88CC vacuum tubes are used in the preamp stage to achieve the warm, mellow sound you can only get from tubes


    • A pair of Toshiba bipolar power transistors provide strong, driving power and high-quality sound


    • Sifam VU meters provide precise metering with a classic feel that matches the warm, analog tone from the tubes


    • Custom-made R-Core transformer counters spikes and instability in the power line, providing consistent, high-resolution amplifier performance with distinctive hybrid sonic characteristics


    • Lundahl transformers, Nichicon electrolytic capacitors and WIMA polyester capacitors are used to provide the best sound quality possible


    • Eight headphone jacks with choice of four different output impedances (0.1, 33, 82 and 120 ohms x 2) give you control of the sonic presentation without the extra noise that might be introduced by an impedance selector switch


    • Two analog (unbalanced RCA and balanced XLR) and two digital (USB and SPDIF digital coaxial) inputs allow the amplifier to be used with a wide range of equipment


    • Includes power cable


System Requirements Computer with a USB 2.0 port
CPU Intel Core2 CPU 2.2 GHz or equivalent
RAM 32-bit OS 2 GB or more, 64-bit OS 4 GB or more
Compatible OS Windows 7, Windows 8, Windows 8.1, Mac OS X10.9
Type Preamplifier stage: vacuum circuit Power amplifier stage: Class A bipolar transistor amplifier
Corresponding Headphone Impedance 16 – 600 ohms
Dimensions (excluding protrusions) 100 mm (3.9") H × 332 mm (13.1") W × 327 mm (12.9") D
Weight (body only) 1.0 kg (24.3 lbs.)
Accessories AC adapter