FOR SALE:• Item: • Manufacturer: Audio GD • Model#: NFB-3 DAC • Weight: 11 Lbs • Dimensions: 9.5” x 12.6” x 3.15” (WxDxH) • Colour: Black • Input Termination: USB, COAX 75 Ohms and Optical Toslink • Output Termination: RCA Unbalanced only. • Voltage: 120v (USA) 15A IEC. • Condition: 8/10 • Mechanical defects: NONE • Cosmetic defects: Minor Imperfections. • MSRP: $499.00 • Box/Manual: No Box / No Manual • Accessories: Power Cord. • Repair/Service History: NONE • Upgrades/Mods: TCXO Clock upgrade • Warranty: None provided, Sold AS-IS. • Asking Price: $295.00 • Link to more information: • Reviews: https://darko.audio/2014/04/audio-gd-update-nfb-3-dac-with-ess-sabre-9018-chip/ • Payment Method: Money Order, Cashiers Check, PayPal and Cash.
(Paypal users: Must have verified address with PayPal and pay 3.5% Fees) • Shipping terms: Buyer Pays shipping. USA and Worldwide. Please email with inquiries some restrictions apply. Cash/Local pickup preferred.
Description below: Dedicated Discrete DAC built in ES9018
DSD, DXD support from USB
32bit / 384K Sabre ES9018
32bit / 384K Asynchronous Transfer USB-32 Chip
Fully discrete analog stages without any OPA and couple caps in the signal channels.
Class A power supplies, Total have 7 groups PSUs and 30,000 UF Audio caps for power supplies.
3 channels digital input: RCA coaxial / Optical / USB
DAC output: RCA Specifications might subject to change without prior notice for product improvement.
S/N Ratio 116DB
Output impedance 10 ohm Output Level 2.5V (RCA)
Input Sensitivity 0.5 Vp-p(75 Ohms, Coaxial)
19 dBm (Optical)
Frequency Response 20Hz - 20KHz （-0.2DB）
Support Operate Systems (USB) Windows , OSX
Support Sampling USB model: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz ,352.8kHz,384kHz
Coaxial model: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 192kHz
Optical model: 44.1kHz, 48kHz, 88.2kHz, 96kHz
Power Requirement Version 1: 100-120V AC 50/60 Hz
Version 2: 220-240V AC 50/60 Hz
Power Consumption 15W
Package Weight Approximately 5KG
Dimensions W240 X L320 X H80 (MM, Fully aluminum)
Accessories AC power cord X1 About NFB-3
Simple and short signal transfer is best:
The NFB-3(2014) applies the newest ESS high-end Sabre32 DA chip ES9018 which can support up to 32Bit/384KHz input.
ES9018 in voltage output model, there is -12DB THD+N worst, to be achieve the best performance of ES9018, must work in current output model.
In some other ES9018 built in DAC design, ES9018 output signal have to through 3 step OPAs implement analogy signal process.
The NFB-3(2014) had different design. The ES9018 feed to the ACSS circuit by balanced model without any OPAs.
The ACSS circuit naturally working in current model and have design difference current input, it can transfer the ES9018 current signal to output and implement the I/V conversion in current model in one ACSS amp. And this ACSS amp only have one current gain stage, the ES9018 output signal only through one stage can arrive the output stages.
The shortest signal journey can reproduce the best detail and dynamic, and almost without sound coloration, it can show the real performance of the ES9018.
So our ACSS design is the best combo with ES9018 achieve the best performance. The ACSS also is a non-feedback technology made with fully discrete amplifiers. Most people know the global feedback design can offer better specs in test measurements, and non-feedback can't do well in test measurements but can offer better sound for the human's ears. Here is a conflict of the classic circuits.
But the ACSS opens a new field, it can offer a least coloration sound which is more neutral with very low distortion and high linearity. So it can retain the dynamics, detail and neutral sound but not sound bright or harsh.
The output buffers are Non-feedback. For low impedance, we applied a diamond output stage which is quite less colored than most conventional circuits.
The DAC is without couple caps to avoid coloration. There are two OPAs built in as the DC serve to keep the DC offset.
The 32bit / 384K USB interface outputs a I2S signal to ES9018. Multi-ply Class A power supplies are the key of sound:
NFB-3(2014) applies the excellent DA chip ES9018 and excellent analog output stages, but these are not the only keys of the best sound. The power supply is most important. Even applying the best DA chip and the best amp, if matched to an average power supply, the total sound may still be average or sound musical but can't be neutral and detailed. That is why it is easy to find hi-end grade gears maybe without the best chips, but with plenteous dedicated DC supply circuits.
The NFB-3(2014) uses A total of 2 groups class A PSUs and 5 groups linear PSUs power supply for all digital and analog circuits.
To achieve high S/N, the control circuit is powered with separate regulator. "Inputs? There are three: optical, coaxial/BNC and USB. The latter is hosted by a VT1731 receiver which Audio-gd claim to be “one of the best USB interface chips in the world” with “15x less jitter than the TE7022 [chip]”. Regardless of copywrite hype this is another budget DAC manufacturer taking USB input quality as seriously as Schiit."
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