Audio-GD - A1 Power Amplifier (Balanced Discrete Power Amplifier)

Audio-GD A1 balanced power amplifier is designed without any compromises using the best components on the market! Like all products of Audio-GD the amplifier is entirely made by hand and for a reasonable price. The analogue amplifier stages of this amplifier are non-feedback and DC coupled without any opamps, all discrete. The power supplies of this amplifier are feeded by a huge transformer, Audio-GD uses a technique that is  unique in this price range, and designed using "Diamond Cross output stages". This power amplifier is a true balanced non-feeeback ACSS solution and delivers 125W per channel @ 8 Ohm and 250W per channel @ 4 Ohm speakers. This pure analogue desinged amplifier sounds Neutral, detailed and musical. 

SUMMARY

• Slim design; medium size Form Factor.
• True Balanced ACSS Power Amplifier
• 8x Output transistors in total 1200W output power
• Per channel 125W @ 8 ohms output power
• Diamond gain stages and pre-buffer stages working in pure class A
• Output transistors stages work in high idle current state.
• Diamond Cross output stage design avoids "switch distortion".
• Non- feedback ACSS analogue amplifier design
• The capacitance of the whole machine is in total 80,000 uF
• Completely separated design to achieve best channel seperation.
• Audiophile grade components, WIMA caps, custom order NOVER (UK brand) caps, all audiophile grade input & output sockets and gold IEC socket. 

Matching preamplifiers:

• NFB1 AMP; R-28; NFB28.XX; 

INPUTS

• XLR 3-PIN Balanced

• ACSS mini Balanded

OUTPUTS

• 2 x Speaker (LEFT & RIGHT) Neutrik output IEC sockets.

ACSS TECHNOLOGY

Poweramp A1 is a discrete design applying the latest ACSS technology which improves the XLR connection to be able to sound as good as the ACSS connection. It seems complex, but in fact it is most straightforward design in the world. There are a lot components in the power supply providing rich and clean sound. The Poweramp A1power amp has a single “voltage" gain stage to process signals, but works fully in ACSS mode; which in fact is a current gain stage instead of the standard voltage gain stage. The voltage gain state applied by almost all manufacturers requires at least two or three voltage gain stages. We implemented most elementary and shortest signal journey resulting most neutral and cleanest sound.

Poweramp A1applies ultra-low distortion single stage ACSS amplifier soldered directly on the motherboard to reduce noise floor even more. The gain stages and pre-buffer stages are all designed to work in pure class A .

The diamond cross output stage design avoid "switch distortion" as good as the best class A amp.

The ACSS is a non-feedback technology is designed with discrete amplifiers. Most people think the feedback design offer better specs in test measurements, and non-feedback isn’t as good. Putting the measurements aside, non-feedback offers more pleasant sound for the human's ears. This is a pyridoxal conflict of classic circuits. Our developed ACSS named technology opens a new field: It can offer a neutral
sound with very low distortion and high linearity. Retain the dynamics, detail and neutral sound without sounding bright or harsh.

All signal gain are in current mode, achieved by the unique, superb open-loop multiple output current mirror. Incomparably precise and ultra-low distortion in the gain signal is the result. The signal path is balanced throughout and all transistors work in class A mode.
　
Power Supply
Massive use of high power parts and robust power supply guarantees vigorous current output that drives almost every loudspeaker.
Poweramp A1 applies two channel diamond non-feedback output stages composed of 4 transistors, every transistors can handle 150W / 15A . The power supply capacitance is over 40,000uF per channel.

The Poweramp A1 supports very wide frequency band with excellent phase distortion, and boost the amp to have excellent detail and dynamic reproduction.

Inputs:
Poweramp A1 has XLR balanced inputs and top grade proprietary ACSS current signal inputs.

Components:
Solely audiophile grade components being used, e.g. 0.1% KOA resistors, WIMA caps, and custom ordered NOVER (UK brand) caps.