PS Audio DirectStream DAC

Description

Stereophile Recommended Component 2015 – PS Audio DirectStream DAC

The PS Audio DirectStream DAC is one of the most remarkable DACS ever built as all the major reviewers agree. Hand written, discrete, perfection based conversion that uncovers all the missing information hiding in your digital audio media. CD’s, streaming audio, high-resolution PCM or DSD based media are expertly upsampled in the DirectStream to twenty times DSD rate and output as pure analog directly into your amplifier or preamplifier. There has never been a better sounding DAC at anywhere close to the price of DirectStream. It is the first choice of thousands of critical listeners worldwide, and with its ability to accept our free Operating System upgrades, will never become obsolete.

• DESIGN – DirectStream converts every input signal, both PCM and DSD, to single-bit, high sample rate 20X DSD signal. Use of a FPGA rather than an off the shelf DAC chip provides immense processing power, resulting in complete lack of digital glare, and allows the owner to download OS updates as they are released.
• APPLICATION – DirectStream is the heart of a reference quality digital audio based system. It handles all PCM sources up to 352.8 kHz, and DSD 64 and 128 (USB and I2S) and DSD256 (I2S only, with the Sunlight OS). Its zero-loss digital volume control allows it to be used as a preamplifier, directly feeding a power amp. Include the Network Bridge to stream Qobuz, Tidal, and Spotify. Roon ready.

 

View Owners Manual >>

 

Awards

• 2019 Class A+: DirectStream in Digital Processors from Stereophile
•  2018 Recommended Component Award from Stereophile
•  2017 Recommended Component Award from Stereophile
•  2016 Golden Ear Award from The Absolute Sound
•  2016 Brutus Award from Positive Feedback
•  2016 Recommended Component Award from Stereophile

 

Technology

Class A+ Stereophile rated DirectStream DAC converts any digital input format from CDs, servers, and streamers, into a pure DSD format and outputs near-perfect analog directly to your power amplifier or preamplifier. Whatever the format, sample rate, or the medium, DirectStream provides a pure output that fulfills the promise of high-resolution analog performance from digital sources. DirectStream is the work of digital audio genius, Ted Smith. Unlike conventional DACs that rely upon off the shelf DAC chips, DirectStream is hand written onto a FPGA (Field Programmable Gate Array). This allows far more precise and accurate processing of the digital signal, resulting in significantly better sound quality and upgradeability in the field. Every six months or so, Ted Smith’s continual research into digital audio reproduction nets another breakthrough in performance. DirectStream DAC owners are given it free in the form of a downloadable upgrade. In this way, DirectStream owners can be assured that their unit will continue to improve over time, and never become obsolete. Hear what’s been missing in your music for all these years. If you know the sound of music and instruments, and want to hear what’s been missing on your discs, then this DAC is right for you.

 

DSD Conversion

Converting the ones and zeros of digital audio into music we cannot distinguish between live or recorded is an art. Most of today’s sophisticated DACs are IC based instruments using off-the-shelf-chips that rely upon Multi-bit Sigma-Delta functions to process the incoming digital audio. While these are relatively simple to design and produce, they rarely give the best sonic results. DirectStream takes a different approach by first converting all digital audio signals into a purer form of digital audio known as DSD. DSD is a far more analog-like encoding and decoding process than the classic CD based PCM. In fact, most modern A/D converters used to make recordings are DSD based already. DirectStream takes both PCM and DSD, upsamples the data and converts to single-bit DSD and then outputs pure music regardless of input format for the data. The results of this design can be heard in increased musical information presented to the listener at every opportunity. When you listen to DirectStream you never are accosted by added bright, hard glare in the music as happens with many active designs. Instead, clean, pure music flows from the DirectStream directly to your preamplifier or power amplifier.

 

Output & Volume

Most modern DACs use some form of active tube or solid state output stage to amplify, filter and drive the DAC’s output. DirectStream takes a different approach: passive. In one of the simplest, elegant and musically correct executions of an output stage, high-speed class A video amplifiers are used as the final switch feeding a high-performance passive audio output transformer. The transformer is specially designed to act as both the galvanic isolation between the DAC and the outside world as well as the primary low pass filter required to present a perfect, low distortion, low noise output signal that is fed directly into the DirectStream’s zero-loss volume control. Designer Smith perfected a 100% bit-perfect volume and balance control that’s built into DirectStream, enabling users to control the output level when feeding directly into a power amplifier or preamplifier. The ability to eliminate the preamplifier in the system without any resolution loss is a major benefit to DirectStream’s outstanding musical performance. Imagine going to a recording studio and listening to a master tape of any recording made. This is the experience DirectStream provides its owners who enjoy a renewed sense of enjoyment and discovery when listening to everything in their library: CD’s, downloads, DSD.

 

Features

• 100% DSD BASED D-A CONVERTER
• UPGRADABLE VIA SOFTWARE RELEASES
• VOLUME, BALANCE CONTROL BUILT IN
• UPSAMPLES PCM AND DSD TO 20x DSD RATE
• DXD SUPPORT
• PASSIVE TRANSFORMER COUPLED OUTPUT
• IMPROVES IMAGING + SOUNDSTAGE
• DIRECT SIGNAL PASS WITH 1x MASTER CLOCK
• HANDWRITTEN FILTERS, PROCESSORS, SAMPLERS
• IMMUNE TO OUTSIDE SOURCE JITTER PROBLEMS
• INCREASED DIGITAL HEADROOM
• NO OFF-THE-SHELF IC-DAC CHIPS USED
• UNCOVERS DETAILS USUALLY MASKED BY PCM PROCESSORS
• 7x DIGITAL INPUTS
• MQA + TIDAL READY WITH OPTIONAL BRIDGE II
• FULLY BALANCED FROM INPUT TO OUTPUT
• COLOR TOUCH SCREEN

 

SPECIFICATIONS

Physical
Unit Weight	22 lbs [9.97 kg]
Unit Dimensions	14” x 17” x 4” [ 36cm x 43cm x 10cm]
Shipping Weight	31 lbs [14 kg]
Shipping Dimensions	20.5”x 24” x 10” [52cm x 61cm x 25cm]
Power requirements
Input Power	Model specific 100VAC, 120VAC, or 230VAC 50 or 60Hz
Power Consumption	30W
Digtial audio inputs	I2S(2), Coax, XLR Balanced, TOSLINK, USB, Network Bridge slot
Sample Rates	I2S, and USB — 44.1kHz to 352.8kHz 16bit, 24bit, DSD 64, DSD 128 TOSLINK – 44.1kHz to 96kHz 16bit, 24bit XLR (AES/EBU)S/PDIF (coax)– 44.1kHz to 192kHz 16bit, 24bit, DSD 64
Analog Audio Output
Connector	RCA/XLR Unbalanced /Balanced (X2)
Output level, low	0.282 VRMS Balanced 0.141 VRMS Single Ended
Output level high, maximum	2.818 VRMS Balanced 1.414 VRMS Single Ended
Output Impedance	100Ω/200Ω
Frequency Response	20-20KHz +/- 0.25dB
THD&IM @ 1KHz (full scale)	<0.03%
Output Stage	Passive audio transformer, fed by high current, high speed analog amps producing double rate DSD.
Data Handling
Format	PCM or DSD
Sample rate (PCM)	44.1kHz, 48.0kHz, 88.2kHz, 96.0kHz, 176.4kHz, 192kHz, 352.8kHz
Word length (PCM)	16b, 18b, 20b, 24b
Data rate (DSD)	Standard (2.8MHz) or Double (5.6MHz) DoP as well as raw DSD on I2S and USB inputs
Input jitter reduction	effectively 100%, residual immeasurable. No input PLLs, FLLs.
Input Processing	170MHz
Signal Processing	50MHz
Synchronous Upsampling, all inputs	28.224MHz
Digital Processing S/N ration	>146 dB
Digital Volume Control	Zero loss of precision
Analog Conversion method	Delta Sigma (DSD) Single-bit double rate
I2S Digital Input
Connector	HDMI
Format	PCM or DSD. DoP on all inputs as well as raw DSD on I2S inputs
USB Digital Input
Connector	USB “B” Type
Format	PCM or DoP v1.1 (DSD over PCM)
Transfer mode	Asynchronous