HiFiMAN Balanced Amplifier Card

The Balanced Amplifier Module was designed with some of the most expensive and high-quality parts on the market today. It uses (4) OPA627 OP-AMPS and (4) OPA634 buffers. By using these high-quality chips, the listening experience produced by the HM-901 is second to none.

This design will work in the balanced mode for earphones/headphones with a 3.5mm TRRS or in standard mode for earphones/headphones with a 3.5mm standard jack. This powerful amplifier module will drive some of the most demanding headphones on the market.

Specifications
Adapted Models: HM901s/901U/802U/650/901/802
Power Supply Voltage: ±8.2v
Power Supply Current: ±20 mA
Maximum Balanced Output (30R load): Low Gain-2.32v(179mw)
Maximum Balanced Output (30R load): High Gain-3.91v(477mw)
S/N: 112±1dB
Frequency Response: 20Hz-20KHz(-1dB)
Maximum Normal Output (30R load): Low Gain-1.45v(70mw)
Maximum Normal Output (30R load): High Gain-2.5v(200mw)
S/N: 109+/-3dB
Frequency Response: 20Hz-20KHz(-1dB)
Output Impedance: 1 Ohm