Shortly after the successful launch of its PM-1 planar magnetic headphones, OPPO Digital has 
released another member of its family of personal audio products – the HA-1 headphone amplifier.
The analogue audio section of the HA-1 is a fully balanced design with an emphasis on keeping the audio signal in the analogue domain once it leaves the DAC. The HA-1 is anchored by a hefty toroidal power transformer, and linear power regulators and filters with custom made capacitors to help ensure that the headphone amplifier has a clean power source with plenty of reserve energy. The fully balanced Class A power amplification section uses “hand-picked and paired discrete components to ensure symmetry”, and a motor-driven volume control knob allows for both manual and remote control volume adjustment.
Its digital inputs include coaxial, optical, balanced AES/EBU, and an asynchronous USB DAC. The USB DAC supports PCM audio up to 384 kHz 32-bit resolution and DSD audio up to 256x the CD sample rate and it uses same ESS 9018 Sabre32 Reference DAC and output driving stage used in OPPO Blu-ray players. The HA-1 is compatible with Apple’s iPod, iPhone and iPad for use as an external DAC, enabling the listener to directly tap into digital music played from these devices.
Retail price of $1199, and the silver version is estimated to be available in June.
