The SDA-2 is an high-performance D/A Converter with pre-amplifier and headphone amplifier. Fully balanced design. Based on XMOS’s latest xCORE-200 series chip-set for USB Audio input and the AKM497, AKM’s third-generation DAC chip for DA conversion and the AK4118 digital audio s/pdif input receiver chip,. The STM32 main control CPU, Xilinx’s large-scale FPGA processing the clock system circuit and digital audio stream. The amplifier is desgin is a 4-way full balanced circuit. Independent discrete class A amp.
PCM supports up to 384Khz, DSD uses native direct solution technology, supports up to DSD512, and all interfaces support DSD decoding.
AKM’s flagship DAC chip, the AK4497EQ supports DSD native direct solution mode. The DSD digital stream does not pass through the internal digital filter and modulator, and works in NOS mode. PCM can also work in NOS mode, which is in line with e.g. HQPlayer design concept.
SDA-2 is the first DAC / preamp / headphone product we developed using following technologies approach:
- USB uses our first generation isolation technology: SCIT technology (Singxer capacitor isolation technique), SCIT technology is a full isolation technology (ground isolation), high-speed signal using 150Mbps isolation chip, low-speed signal using optocoupler isolation It can completely isolate the interference from the PC; the USB version of the high version can basically reach the level of the SU-1 independent digital interface.
- Source synchronization technology and FPGA shaping technology, re-shaping the isolated I2S signal; thus eliminating the additive jitter caused by the isolation chip
- The self-developed clock system uses a femtosecond crystal oscillator as the local reference clock
- Class A discrete amp circuit, full balanced amplification using 8 transistors per buffer.
Two versions are available. Both use ACCUSILICON AS381B femtosecond crystal oscillator AS-318B for main audio clocking, the C version has additional Crystek CCHD-575 femtosecond crystal oscillator for USB INPUT.
Standard Version SDA-2 A – Standard XO for USB INPUT
Advanced Version SDA-2 C – Crystek femtosecond crystal oscillator CCHD-575 USB
- USB – Standard USB-B type
- I2S – LVDS level HDMI
- OPTICAL S/PDIF
- RCA S/PDIF – 75OHM
- AES/EBU – 110OHM
Sample rate: PCM: 44.1KHz,48KHz,88.2KHz,96KHz, 176.4KHz,192KHz,352.8KHz,384KHz
Native & DoP 2.8 MHz (DSD64), 6 MHz (DSD128), 11.2 MHz (DSD256)
Native 22.5792 MHz (DSD512)
Bit depth: I2S output max 32 bit, S/PDIF max 24 bit
1, USB input socket is a standard USB-B type female socket, USB power supply range is 4.5V-5.1V;
2, SPDIF interface input standard S / PDIF signal, input impedance is 75 ohms, AES input impedance is 110 ohms;
3, the power input is 115V/ 230V AC, and the internal 30W O-type transformer is used for power supply;
4, I2S input is LVDS level in the form of HDMI interface, compatible with SU-1 interface;
Output level (0dBFS):
PCM: RCA single-ended output is 2V RMS, XLR balanced output is 4V RMS
DSD: RCA single-ended output is 1.8V RMS, XLR balanced output is 3.6V RMS
Output impedance: 22 ohms (RCA single ended) / 44 ohms (XLR balanced)
Frequency response: 20-20kHz +/-0.2dB
Signal to noise ratio: 125dB
THD+N (1kHz, 0dBFS) 0.00025% at fs=44.1Khz (PCM)
THD+N (1kHz, 0dBFS) 0.00030% at DSD256
Dynamic response (1kHz, -60dBFS) 125dB
Left and right channel separation >125dB
Balanced output noise floor: 2.2uv RMS
Amp balance maximum output power 3480mW@30Ω, 0dBFS
Distortion of the amp balanced output, 0dBFS, fs=44.1Khz (PCM)
75Ω load THD+N -105dB
600Ω load THD+N -110dB
1, Windows 7, Windows 8, Windows 10; 32/64 bit, need to install a dedicated driver
2, Native MacOS 10.6 and later, using the system comes with a driver
3, Native Linux with UAC2 compliant kernel, using the system’s own driver, (tested on Ubuntu and Daphile systems, based on INTEL X86 platform)
4, Android OS 4.2 and above, the device needs to support OTG function, in general, the Android 5.0 system is supported by default, and the following 5.0 recommendations are used with a dedicated player.