Veracity Audio Mystra DAC update

Official update about the Veracity Audio- Mystra DAC…

Veracity Mystra product is a true dual mono design with dual DAC architecture. The dedicated 24bit dual mono conversion handles PCM format without sample rate change.  The stand-alone ΔΣ bitstream reconstruction filter plays back DSD64 and DSD128 natively, without digital processing. The Mystra is a dual DAC which auto-switches with the incoming signal file format: when the DSD is the incoming format it will go to the DSD reconstruction filter.  When PCM is the incoming format it will go to the parallel PCM only DAC. Through direct connection, both engines share only the valve analogue stage, on a ‘one-at-a-time’ basis.

The Mystra DAC is fully featured for any two channel digital audio application: 2 x RCA COAX (optional AES/EBU, BNC) digital inputs, multi-format asynchronous USB input, analogue preamplifier function and stereo RCA and XLR outputs.

To precisely match the output of the DAC to any pre or integrated amplifier, Mystra DAC is equipped with analogue volume control. The non-inductive audio resistors are switched by relays in R2R shunt operation mode, meaning that only two resistors are in the signal path at any volume level. This discrete, stepped attenuator has 87 levels. For purist, minimalistic systems, this volume control will facilitate direct connection to power amplifiers. Volume control and input selector operation is remotely controlled with a custom, handmade handset.

With a total focus on SPDIF signal quality and unique to the design, a new quad differential receiver with jitter rejection was developed. This works with any CD transport and other compatible sources.

The DAC is equipped with a line preamplifier option. An external analogue source can then be linked directly to the DAC valve stage, the latter becomes an active preamplifier with R2R volume control. Analogue input is a pair of RCAs. Output is via main analogue outputs, RCA and XLR.

Mystra DAC features an output for 32Ω – 300Ω moving coil headphones. A minimalistic high current design, solid state driver, takes the signal directly from the valve output and is capable of up to 250mA signal current delivery.

The valve analogue output stage operates in pure Class A.

It is a single ended triode design without negative feedback and has original Veracity topology. It remains true to the source phase of the signal.

The valve signal amplifier features bias reference generator and active triode loading. Here one valve triode works as a current source to another valve triode for pure, symbiotic operation.

The DAC features low impedance, high current drive audio outputs. Jensen Copper foil audio capacitors are used for signal. Both single ended RCA and XLR audio outputs are coherent with any amplifier with RCA`s 209Ω and XLR`s 600Ω output impedance.

The valve stage consists of a pair of 6SN7 signal drivers, a pair of ECC82 output drivers and a pair of CV574 full-wave valve rectifiers. To personalize the sound, Mystra DAC includes ‘valve rolling’ flexibility, so users may match their tonal preferences. Information about valve replacements are published on the Veracity website in their Why+FAQ section.

To keep the signal path pure and simple, non-saturating, jitter free- analogue relay switches are used for all signals. Cmos, mux transistor signal switching is not used.

Veracity Audio believes that power supplies are the most important element of audio design. With the Mystra DAC, they have not only separated the digital and analogue power supplies but also the left and right channels. This was done from ground-up including the 3 independent mains transformers chosen from Talema. Discrete Schottky rectifiers supply power to strictly linear, ultra-low noise voltage regulators. Analogue stage is powered directly from full wave, twin valve rectifiers. Each power recipient has its own power supply, including the internal linear power supply for the USB interface. These 20 power supplies are fast and capable of high current delivery featuring separate power rails with dedicated decoupling for each power load. A system of multiple choke filters, ultra low impedance film and organic polymer capacitors is used, to provide the purest power flow possible. The DAC also features a built-in, CLC mains filter selected from Schurter.

The unique Veracity casework is three Faraday cages joined together into a monocoque structure. This provides the circuitry with an extremely high-stability mechanical base, EMI & RFI screening and resistance to vibration. The casework is polymer coated. The internal aluminium/viscoelastic rubber lining, additionally protects against vibration. The aluminium top cover and removable valve cover are the only structural parts fitted with screws. The DAC is also directly fully grounded via the safety earth pin in the fused IEC socket. Direct grounding gives the highest electrical safety and a direct escape route for EMI/RFI interference.

95% of parts are sourced in the UK and the DAC is totally hand-built in England. Veracity uses the latest analogue and digital components and thoroughly modern engineering. Every component is selected purely for its sonic characteristics and reliability. Each unit is soak-tested for 24 hours prior to shipping. Veracity is confident with the reliability of its products and issues a three-year guarantee from delivery date.

Format: PCM or DSD 

Sample rate (PCM):  44.1kHz, 48.0kHz, 88.2kHz, 96.0kHz, 176.4kHz, 192kHz 

Word length (PCM) 16bit, 24bit 

DSD rate:  SACD standard (2.8MHz) DSD64 and DSD128 double rate (5.6MHz-6.144MHz) 

DSD transfer support: raw (native) DSD or DSD over PCM (DoP) into USB input with ASIO/WASAPI driver 

D/Analogue conversion method: 

PCM- multibit hybrid

DSD- 1bit ΔΣ, analogue filter  

PCM processing S/N ratio >120 dB 

DSD reconstruction filter S/N ratio >112 dB

Digital audio inputs 

Coaxial SPDIF x 2

USB x 1

USB digital input details

Connector: USB type B 

Format: PCM and raw (native) DSD with ASIO driver or DoP v1.1 (DSD over PCM)

Transfer mode: Asynchronous

O/S device name: combo384/ASIO , Amanero Technologies/WASAPI, KernelStreaming 

Input sample rates and format

SPDIF: (PCM) 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz/16bit, 24bit

USB: (PCM) 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz/16bit, 24bit. (DSD) DSD64(2.82MHz), DSD128(x 44.1- 5.64MHz), DSD128 (x 48- 6.14MHZ)

Analogue audio input

RCA (pair) x 1, line level signal input, 

Sensitivity: 100mV – 2.81Vrms

Input frequency range: 5Hz – 100kHz +0/ -2dB

Analogue audio outputs

RCA unbalanced x 1 pair, XLR (Jensen passive) balanced x 1 pair

Output level minimum: step 1- 0.0001V (-77.78dBu)

Output level maximum: step 87- 3.777V (+13.76dBu)

Output impedance: 209Ω (RCA), 600Ω (XLR)

Headphones output

1 x stereo, 6.35mm Jack socket

Support for 32Ω to 300Ω headphones

Power: 150mW (depends on headphone impedance)

Maximum output current: 250mA

Headphone driver uses signal directly from valve outputs. Output level is controlled via main volume 

Frequency response

PCM sampled at 192kHz: 5Hz – 40kHz +0/-3dB

PCM sampled at 44.1kHz: 5Hz – 20kHz +0/-0.2dB

DSD64 – 5Hz – 50kHz +0/-3dB

DSD128 – 5Hz – 50kHz +0/-3dB

THD at 1KHz (2.77V, +11.06dBu): <0 .08="" p="">

www.veracityaudio.com/