This is one Assembeld & tested amp board. with the ALPS 27 volume potentiometer.
Works voltage: AC115V or 230V ( has a switch on the board for choose input voltage)
requency response:12HZ~50kHZ（+0dB，-1dB）；12HZ~120kHZ（+0dB，-3dB）
Voltage gain:21dB
SNR>101dB
Conversion rate: > 35V/mu S
static electricity:240mA
PCB size: 200mm*130mm
Heatsink height about 48mm.
This board can be used as headphone amp or preamp,
work Current: Total 125mA can supply 100ma for the load
