Audio-GD - NFB1-AMP - Balanced Pre / Headphone Amplifier
NFB-1AMP is a true balanced design applying the newest ACSS design based on the ultimate Master-9 which can improve the XLR connection to sound as good as the ACSS connection. They seem complex , but in fact they are the most simple design the world has ever had , their a lot components to process the power supply. The simplest and shortest signal journey brings out the most neutral and least colored sound.
NFB-1AMP applies very low distortion single stage ACSS amplifier and soldered directly on the motherboard. It is a fully class A preamp / headphone amp and applies class A power supplies.
Fully balanced class A design built by discrete analog stages without any OPA or coupling caps in the signal channels.
Non- feedback ACSS analog output stage.
Uses high grade parts and exactly matched transistors.
Four-channel 100 steps digitally controlled relay-based volume control avoids channel imbalance and improves sound quality .
Discrete class A Power supply
Exponential volume characteristic
Drives headphone output ot 8000mW at 40 ohm output
All OCC and hi-end grade components, including DALE resistors, WIMA caps, custom order NOVER (UK brand) caps.
Memorizes all settings and resumes the last settings when powered on.
The pure analog technical design is difficult (impossible?) to upgrade. The 2019 Edition has got new firmware to offer additional functions and easy control of the functions. Sound quality is same with previous generation.
1. XLR balanced
2. RCA single ended
3. ACSS balanced
4. RCA single ended
5. XLR balanced
XLR inputs can be replaced by RCA single ended inputs
ACSS input can be replaced by RCA single ended input
Preamp / DAC output : XLR / RCA / ACSS (variable)
Headphone output : 4 pins XLR / 6.3MM SE
Audio-gd NFB-1AMP Headphone Amplifier Review
AUDIO-GD NFB-1AMP REVIEW (The Awaited)
The DAC consist of A tuned low noise, low flux leakage, R-cores transformer. In total 65W power to supply all digital parts and the left and right analog boards. The DC power is distributed separated power regulators. All are pure class A low noise shunts; fed by linear power supplies. Resulting in ultra-high speed and clean power for all individual parts.
HIGH PRECISION VOLUME CONTROL
Volume control consist of relay-controlled attenuators. Fully-independent, fully-balanced stereo volume controls. The volume controls feature consist of high-precision 0.05% tolerance film resistors and golden contact relays. Buffered inputs and outputs.There 4 channels volume boards are built in the unit to achieve ultimate balanced volume control. They are controlled by a digital signal controlling the high quality relays switching the precision resistors in analog area.
Audio-GD lineair volume characteristic
Volume steps in comparison to standard volume control
Quality of volume control is very important in balanced applications . It have to effectuate the four channels to work as synchronous as possible to keep the balanced signal in perfect shape. In traditional volume controls the balanced output will introduce distortion which will negatively influence sound quality and performance and might even get worse than a single ended setup and waste the advantages of balanced designed solution.