Audio-gd products had design and test based on the AP SYS-2722 (The top-drawer professional equipment in world)


Fully balanced design, the gain stages and pre-driver stages work in class A and are built with discrete analog stages without any OPA or coupling caps in the signal channels.
The output transistors stages work in high idle current state . The Diamond Cross output stage design avoids "switch distortion" as good as class A amps.
Non- feedback ACSS analog amps.
2 group analog inputs:  XLR / ACSS
Applies 48 pieces of ON Semiconductor  “the King of transistors” MJL4281/4302. Supports 250W X2 (8 Ohms) output.
 The capacitance of the whole machine reaches as high as 220,000 uF, Two 750W (Total 1500W) core transformers and two R core transformers , Separate power supplies for the right and left channels.
A total of 4 groups of high-quality class A parallel connection PSU's supply the gain stages.
Applies all audiophile grade components, including DALE resistors, WIMA caps, custom order NOVER (UK brand) caps, all audiophile grade input & output sockets and gold IEC socket. Applies the round-corner style chassis which has lower syntony, or vibration. Between the transformers and signal amps resides a thick metal board to avoid disturbance.


Advice:    1, Master-2 has extremely high fidelity; its SQ is neutral. It can show how good or how bad a recording or source is.
                     2, It is better not to stack gear on top of each other, if it's necessary to stack Master-2 on other gear, place a piece of paper or other insulating material on top of the other gear, as the Master-2 has conductive aluminium feet.
                     3, Attention must be given to matching suitable power and signal cables.

A review of our preamp and power amp from John Darko.
http://www.digitalaudioreview.net/2011/09/audio-gd-c39-mk3-pre-and-c10-se-power-acss/