Friday, January 1, 2016

Valve Audio Devices DAC-12 R


Two distinct digital to analogue converters in one chassis – one for PCM, one for DSD

Dual mono PCM with 24bit/192kHz and 126dB dynamic range (hybrid converters, current steer, 7 D/A blocks per channel, mixed method; R ladder/Σ-Δ)

Separate DSP-free DSD-to-analogue conversion

VAD system is based on filtering DSD’s raw PDM bitstream to reconstruct the analogue waveform (designed for DSD only; 1bit direct, 6th order Σ-Δ with LPF)

DSD64, DSD128 native playback of 2.8 – 6.2MHz DSD from USB input

Dual mono triode valve analogue output

User controllable oversampling for PCM data

NOS mode (NX) developed especially for CD Audio resolution: 16 and 24bit PCM 44.1/48kHz sample rate; all digital inputs

MX mode – 2x oversampling; DAC plays PCM 16/24bit/44.1 to 96kHz from all digital inputs

HI mode – 4 x oversampling; DAC plays PCM 16/24bit/44.1 to 176.4kHz from SPDiF input and up to 24bit/192kHz from USB

DAC is free of upsampling in PCM and any digital manipulation in DSD

Audio streaming modes accepted from your computer/server: ASIO Direct, WASAPI /Exclusive(Win7/8), Kernel Streaming DoP, ASIO DoP; Developed and tested with JRiver18,19,20, Audirvana+, HQPlayer

Automatic format switch – DAC ‘sees’ which music format is coming from computer or music server and automatically connects the relevant conversion platform (DSD for DSD, PCM for PCM)

Full integration with mixed playlists/formats music servers

DSD playback automatically adapts to DSD rate

Remote controlled digital inputs, preamplifier input, volume, mute, standby, HT bypass input

1x multiformat USB and two coaxial digital inputs for traditional CD transports (AES/EBU, TOSlink option)

R2R-ladder gain/volume control based on non-inductive resistor network controlled by logic circuit and Takamisawa signal relays. Only two resistors in signal ‘path’ at any given time- manual and remote controlled

Line pre-amplifier input. Preamplifier input works with volume control

HT bypass input via extra pair of RCA s (signal goes directly to valve stage bypassing volume control, output via main SE outputs)

Point to point engineered valve output stage on dedicated sub-chassis

Topology; SE, grounded cathode amplifier cascading directly into cathode follower, pure class A, no NFB/PFB, low output impedance (Z out;100 ohm),  high current drive – output via main SE outputs

Silver signal wiring

Non inductive Holco, Dale resistors thorough

Special selection of signal output capacitors, long researched for the sound in VAD circuits (paralleled; Copper/waxed paper in oil, aluminium in Teflon and Silver mica)

Full dual mono, CRCRCRCC(MKP)LCCC(PIO, MKP) power supplies for valve circuits with total of 3060uF for valves anode supply

Included default set of valves; front pair 6SN7/E88CC/CV574,  6SN7 Raytheon or JAN Phillips 6SN7GT or Psvane 6SN7, middle pair E88CC Tesla or Brimar and pair of CV574 NOS rectifiers

Custom preferences accepted for valve types used in our circuit. The DAC can be build/optimized also for different selection of triode signal valves (please contact for details)

Function indicators (Optic fiber guided LEDs in 2 available colours to choose (red or blue)

Full compatibility with Windows and Mac OS (on Win7/8 Wasapi, ASIO or kernel streaming)

Automatic, ultra-fast (80 ms) `click/pop` reduction system for DSD playback + remote/manual mute

UAC2.0 compliant – Linux ready

VAD ® monocoque casing with selection of milled aluminium black or silver front panels or wood. Wooden fronts are crafted to order by renowned instrument maker in Northampton UK. Complementing the wood are solid brass controls. Machined aluminium controls in relevant colour (black or silver) for metal fronts.