The DAC 8 DSD design incorporates more than 20 years of experience creating digital audio components of unsurpassed quality. The result is a universal device – not just an external sound card for a computer, but a device capable of turning digital audio data of any kind into an analog signal that meets the highest standards. At the same time, engineers did not forget about ergonomics and design.
The T+A DAC 8 DSD DAC works with signals up to DSD 512, and the device contains a DSD converter of its own design, built on discrete elements – it is a 1-bit DSD DAC (True 1-bit DSD DAC). For the PCM signal, a unique processing circuit is used – 4 separate PCM DACs per channel. All this works in conjunction with a precision clock generator and separate power circuits for the digital and analogue sections.
The preamplifier section of the T+A DAC 8 DSD is completely analogue. Note that the DAC 8 DSD is equipped with an audiophile headphone amplifier that easily controls high-impedance headphones.
The base of the DAC 8 DSD is a square with a side of only 270 mm, the height is 95 mm. The housings are all aluminum, with the top and bottom covers made from 6mm plate, and the side walls and front from die-cast profiles. The rigid body thus obtained is mounted on damper legs. The front panels can be called examples of utilitarianism. On the facade of the DAC there is only a matrix display, eight buttons for selecting inputs and the type of digital filtering, plus two more that form a volume control, as well as a 6.3 mm “telephone” output.
You can connect the DAC 8 DSD via either an unbalanced or a balanced bus. The DAC, in addition to the corresponding (RCA and XLR) outputs, has five coaxial (4xRCA and 1xBNC), optical (Toslink) and balanced (AES/EBU) digital audio inputs and one coaxial output, the impedance of which is only 22 Ohms. Of course, there is also a USB B input.
The seriousness of the developers’ intentions is also evidenced by the presence of separate power supplies for the analog and digital circuits of the DAC. The signal level at the outputs is controlled using a complex analog circuit, which allows you to maintain sound dynamics even at low volumes.
If desired, the regulator can be disabled by using two relays with gold-plated contacts. All inputs, except optical, accept signals up to 24/192 (Toslink reads data no higher than 24/96). The USB input operates in USB Audio Class 1 mode with a signal up to 24/96 or in USB Audio Class 2 mode (a signal up to 24/192 is received), and you can choose synchronous or asynchronous operation, which requires installation of a special driver on the PC.
Digital-to-analogue conversion in the DAC 8 DSD is carried out by eight 32-bit Burr-Brown DACs operating in a dual balanced circuit. This solution allows you to compensate for any nonlinearity during processing, and reduce the background noise level by 6 dB. Resampling is performed by a 56-bit processor using algorithms developed by T+A specifically for this circuit, which reduces jitter. Other effective measures have been taken to combat it.
The signal is converted in two stages. First, the audio data itself is extracted from the received stream and processed by a PLL (phase-locked loop) circuit in order to save it from gross temporary errors. The data is then analyzed by a special microprocessor, and if it meets the specified frequency and stability criteria, the DAC 8 DSD DACs are switched to their own extremely accurate clock pulses. (The generator of the latter is completely independent of the signal source, which reduces to zero jitter generated by the computer and resulting during signal transmission.
Synchronization pulses are generated by two quartz emitters – one produces a signal for files with a sampling frequency of 44.1/88.2/176.4 kHz, the second is for 48/96/192 kHz files.) If the input stream does not meet the above criteria, it again undergoes PLL processing, and the residual jitter is reduced by 4 times.
Digital filtering is carried out using Bezier transforms, as well as using FIR filters – standard and with a steep decline in characteristics. You can select the desired filtering from the front panel of the DAC or from the remote control. It is possible to invert the phase of the input signal or expand the bandwidth of the output signal (up to 120 kHz).
Analog circuits, galvanically isolated from digital ones, are assembled on discrete elements without the use of operational amplifiers. The linearity of their characteristics is ensured not by the great depth of feedback, but by the high quality of the components.
T+A DAC 8 DSD Features:
DAC for PCM Features: Dual differential digital-to-analog converter with four Burr-Brown chips (32-bit/384 kHz) per channel; for DSD: one-bit T+A True 1 Bit Converter (DSD64/128/256/512)
Upsampling 56-bit DSP with four resampling algorithms to choose from: FIR short, FIR long, Bezier/IIR, Bezier
Analog filter phase-linear Bessel filter 3- first order with the ability to expand the bandwidth from 60 kHz to 120 kHz
Switchable analog volume control yes
Channel balance adjustment yes
Frequency range PCM (44.1 kHz): 2 Hz – 20 kHz; PCM (48 kHz): 2 Hz – 22 kHz; PCM (96 kHz): 2 Hz – 40 kHz; PCM (192 kHz): 2 Hz – 80 kHz; PCM (384 kHz): 2 Hz – 100 kHz; DSD64: 2 Hz – 44 kHz; DSD128: 2 Hz – 60 kHz; DSD256: 2 Hz – 80 kHz; DSD512: 2 Hz – 100 kHz
Harmonic distortion less than 0.001%
Signal-to-noise ratio 116 dB
Channel separation 110 dB
Maximum output voltage/output impedance 2.5 V/22 ohms (RCA); 5 V/22 Ohm (XLR)
Inputs 4 coaxial (up to 24 bits/192 kHz), BNC (up to 24 bits/192 kHz), optical (up to 24 bits/96 kHz), balanced AES/EBU (up to 24 bits/192 kHz), asynchronous USB port (up to 32 bit/384 kHz, DSD64/128/256/512, for MAC OS – up to DSD128)
Outputs balanced XLR, unbalanced RCA, coaxial, 6.3 mm for headphones
Other switching interface SYS IN for connecting signal sources (to be used in the future), CTRL socket (RS-232) for software updates and control via integrated Crestron/AMX systems Power
supply separate power supply for digital and analog parts
Power consumption 15 W, in standby: less than 0.2 W
Remote control T+A F8
Dimensions (WxHxD) 270x95x270 mm
Weight 4 kg
