GUSTARD DAC-X20 Pro Black Finish, No USB

One of the best kept secrets in the high-performance DAC category, Gustard's DAC-X20 PRO offers top-shelf parts throughout,  high-performance ESS Sabre digital processing chips, ACCUSILICON Femtosecond Crystal oscillator, along with an excellent features set.  Robust build quality with a full aluminum chassis, a dual mono design with twin toroidal power transformers powering each channel independently, along with dual ESS top-end Sabre ES9028PRO DAC chips.  This chip is used in many high-performance audio DACs.  
Full remote control function changes input, and volume, so the X20 Pro can be used as a digital preamp.  
Coaxial, Optical, AES / EBU and BNC digital inputs all operate at 16-24bit / 44.1, 48,88.2,96,176.4,192 kHz PCM format.  
DSD Native: DSD64, DSD128, DSD256, DSD512; DOP DSD: DOP64, DOP128, DOP256, DOP258, DOP258, DOP256
Single ended, and fully balanced analog outputs.  The jaw-dropping performance and robust build of the X20 Pro, in this price category, simply must be experienced to be believed.  Many consumer reviews online to source with a Google search.  
This unit is in absolutely pristine condition, with only a few months use in a primarily analog system.
Here are a few technical details on the X20 Pro from the web:
X20pro technical characteristics:

• The left and right channels independently decoded with dual ESS  ES9028PRO chips.   •  DAC chips are independently powered and independently grounded for optimum performance without interference.
• The first domestic use of adaptive master clock technology.  
• CPLD programmable logic chip, self-built logic function of the digital integrated circuits, clock management,   •  2nd PLL digital shaping, DOP demodulation, PCM / DSD de-pop switch exclusive technology for excellent sound quality. 
• Digital simulation of each adopt a customized 50W audio dedicated ring transformer,   completely independent power supply without disturbing each other;
• Native fully balanced architecture, without any conversion, a complete four-way output;
• Analog LPF circuit using independent development of discrete lines, carefully adjust the parameters of each level in order to achieve the best working condition;
• High-quality digital volume control makes level setting simple.  
• Full interface support DSD hardware solutions:
IIS support DSD64, DSD128, DSD256, DSD512 hardware solution;
SPDIF, Optical, AES / EBU support DSD64 hardware solution (DOP mode);
• Extensive digital filtering
There are seven kinds of PCM: M-SHARP / M-SLOW / L-SHARP / L-SLOW / HYBRID / APODIZING / BRICKWALL,
DSD has four kinds: 47K / 50K / 60K / 70K;
• USB uses XMOS's USBAUDIO dedicated chip U8 (XU208 and U8's core is the same), supports PCM384 DSD256
Adjustable screen brightness.     • All aluminum chassis, the surface drawing, full silver (sub-white) and all black two colors to choose from;
• Dimensions -- 15" wide, 10.2" deep, 2.6" high; • International voltage AC100V-240V (manual adjustment);
• Frequency response: 20Hz-20kHz +/- 0.08dB • Line Output: RCA Output Level Single-Ended 3.0 Vrms @ 0dBFS, Balanced 6.0 Vrms @ 0dBFS • XLR interface definition: US standard (1 ground, 2 hot, 3 cold)
Black / White: X20 = ​​4280 (without USB input);