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NFB-28 (ES9028Pro )

Discrete  DAC+ Headphone amplifier / Preamplifier
With XLR / RCA analog inputs

DSD , DXD support from USB & I2S Input
32bit / 768K Sabre ES9028Pro
32bit / 384K Asynchronous Transfer XMOS U208 Chip


Summarize Use Manual Specs Custom Option Shipping Cost

Specifications might subject to change without prior notice for product improvement.

S/N Ratio


<0.001% (0DBV output level ,SPDIF input )

<0.0005% (0DBV output level ,XLR input )

Output impedance

2 ohm

Output Level

 Headphone output : 19V RMS (balanced , max)
Preamp Variable output (balanced) : 10V RMS (max)
Preamp Variable output (RCA) : 5V RMS (max)

Headphone amp output power level
(Only for  headphone.)
Balanced mode

9500mW / 25 ohm
8000MW /  40 ohm
 3500MW  /  100 ohm
1200MW / 300 ohm
600MW  /  600 ohm

Headphone amp output power level
(Only for  headphone.)
Single ended mode

3600mW / 25 ohm
2500mW / 40 ohm
1100mW / 100 ohm
400mW / 300 ohm
200mW / 600 ohm

Digital Input Sensitivity

0.5 Vp-p(75 Ohms, Coaxial)
19 dBm (Optical)

Analog Input Sensitivity
0.7V  to 5V RMS (RCA)
0.7V  to 10V RMS (XLR)


Frequency Response (DAC +AMP)

20Hz - 20KHz (<-0.05DB)

Support Operate Systems (USB)

Windows, Mac

Support Sampling

 USB / I2S model: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz , 192kHz, 352.8kHz,384kHz
 Coaxial model: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz ,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


Package Weight

Approximately 5KG


Approximately W240 X L360 X H80 (MM, Fully aluminium ) 


AC power cord            X1
USB cable                X1



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