Click here for Home Theatre review
Click here for hi fi+ review
Introducing DirectStream Junior (DSJ), a world class DAC based on the architecture of the Stereophile and Absolute Sound’s Product Of The Year, DirectStream.
DSJ uses the same 20X upsampling FPGA architecture and customized code as PS Audio’s DirectStream DAC, and it is designed and built by the exact same team. The idea behind the DSJ was to offer near-identical performance at a fraction of the cost. How was this accomplished? Lower cost chassis and user interface.
DSJ, like DirectStream, is hand-written, discrete, perfection based conversion that uncovers all the missing information hiding in your digital audio media for all these years. CD’s, downloads, high-resolution PCM or DSD based media are expertly upsampled in the DSJ to twenty times DSD rate and output as pure analog directly into your amplifier or preamplifier. Classic PCM-based DACS, including many of today’s DACS that can also process DSD, tend to cover up some of the subtle musical details buried deep within digital audio music; a problem inherent in their architecture. DSJ solves this problem by employing a pure DSD single-bit approach for both PCM as well as DSD media. This means that your entire library of music can finally reveal all the music and low-level details buried deep within its core – and now, at a more affordable price than its progenitor, DirectStream.
Imagine going to a recording studio and listening to a master tape of any recording made. This is the experience DSJ affords its owners who enjoy a renewed sense of enjoyment and discovery when listening to everything in their library: CD’s, downloads, DSD.
Most of today’s sophisticated DACs are IC based instruments using off-the-shelf-chips that are Multi-bit Sigma Delta based designs. While these are relatively simple to design and produce, they don’t often give the best results sonically. Because they are one-chip systems compromises are made in their architecture that are not found in DSJ’s custom based architecture. DSJ 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.
Most modern DACs use some form of active tube or solid state output stage to amplify, filter and drive the DACs output. DSJ takes a different approach: passive filtering with high-speed, high current analog buffering. 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 for the single-bit, double DSD output of DSJ. When you listen to DirectStream you never are accosted by added bright, hard glare in the music as happens with many op-amp based designs. Instead, clean, pure music flows from DSJ directly to your preamplifier or power amplifier.
Designer Smith perfected a 100% bit-perfect volume and balance control that’s built into DSJ, enabling users to control the output level when feeding directly into a power amplifier or preamplifier. That the volume control is completely bit-perfect means there is no loss of resolution for any volume setting, a feature unique amongst the majority of DACS in the world today. The ability to eliminate the preamplifier in the system without any resolution loss is a major benefit to DSJ’s outstanding musical performance.
Typical high-end DAC designs use more than one master clock. There are often separate clocks for USB, Audio and others, causing challenges for system designers trying to synchronize the clocks. DirectStream obviates the problem by basing the entire design on one master clock of extraordinary high quality. Used is a low phase noise, low jitter clock designed for DSJ by Crystek. Using this advanced approach the need for synchronization is eliminated, jitter levels are reduced and music is delivered with a clarity rarely heard.
Sources have always had a major impact on sound quality with DACS. Transports, computers, CD players, cables all make a significant impact on performance into a typical DAC. This problem has been significantly reduced with DSJ. Now, for perhaps the first time, sources of just about any quality and jitter level sound nearly identical. For example, you can take a cheap $30 DVD or CD player’s digital output, connect with DSJ and have sound quality unthinkable for such a poor source. Performance levels no longer are as dependent on the quality of source or connections; certainly not to the degree they have been in the past. Yes, cables and sources still make a difference, but with DSJ that difference is significantly reduced.
DSJ can match up to either a computer or a home network. If a network connection is desired, DSJ comes equipped with our latest network card, Bridge II. Connect to a NAS or computer with ease, and control your music with an iPad, iPhone, or Android device, and stream and decode full MQA as well as Tidal. You can also connect directly to your computer via USB. USB communication, if handled properly, can have every sound quality advantage of a dedicated CD transport or Network Bridge. DSJ provides a fully synchronous 24-bit 192kHz path for USB based audio, supporting up to 32 bit 192kHz, and single as well as double rate DSD. Using a good quality USB cable between DSJ and your computer, like a quiet MAC Mini, provides an instant media server that can be controlled through any number of handheld devices like an iPod, iPhone or Android using a 3d party controller program. Your music can be managed by iTunes, Bit Perfect, Pure Music or Ammara for ease of use.
A handy feature on DSJ is the polarity (phase) control. This remote control option allows users to select normal or inverted polarity for every input and for every performance. Sources and music have no standard for absolute polarity, a fact easily demonstrated by switching polarities on the as the music plays. Many Audiophiles mark their discs in polarity and out of polarity and are very careful to select the proper polarity before playing each disc. Some CD players and sources themselves invert polarity so that a disc you believe is inverted actually is correct played on a specific device and incorrect on yet another. To fix this problem you can assign each input on DSJ to switch to the proper polarity when you activate that input, through the menu system. Activating this control is the same thing as reversing the loudspeaker connections of both loudspeakers (+ to -) at either the amplifier or speakers. All live acoustic music is in absolute polarity but some recordings may accidentally be made inverted and should sound more realistic when you correct their phase with the switch.
DSJ offers the ability to play directly into either your preamplifier or power amplifier through either its balanced or single ended outputs. You can select the optimum gain setting through DSJ’s setup menu, or from the remote control, to match your amplifier and loudspeaker’s sensitivity. If you choose to go through a preamplifier, it’s easy to set DSJ at maximum level (or any level you wish) to match the preamp’s gain. DSJ’s unique zero-loss volume control maintains full resolution bit-perfect performance at any volume setting from the lowest to the highest levels.
DSJ converts everything to DSD, even PCM before delivering the music to your system. This approach, coupled with careful design, low jitter and a simple and direct signal path has the benefit of uncovering details buried in the music you may not have realized are even there. CDs come alive with subtle details that were never apparent with your older DAC; details you never knew even existed. CDs sound more like high resolution audio than you imagined, closing the gap between higher resolution PCM and DSD copies. No longer do you need to consider replacing your CD library because once you hear what’s truly on your discs, you may not need to upgrade to a higher resolution copy at all. Yes, it is that obvious and significant.
|Unit Weight||18 lbs [8.1 kg]|
|Unit Dimensions||14” x 17” x 2.75” [ 36cm x 43cm x 6.98cm]|
|Shipping Weight||27 lbs [12.25 kg]|
|Shipping Dimensions||20.5”x 24” x 10” [52cm x 61cm x 25cm]|
|Input Power||Model specific 100VAC, 120VAC, or 230VAC 50 or 60Hz|
Digtial audio inputs
|I²S, Coax, XLR Balanced, TOSLINK, USB, Ethernet|
|I²S,S/PDIF, and USB — 44.1kHz to 352.8kHz 16bit, 24bit, DSD 64, DSD 128
TOSLINK – 44.1kHz to 96kHz 16bit, 24bit
Analog Audio Output
|Connector||RCA/XLR Unbalanced /Balanced (X2)|
|Output level (Low)||170mV (-15.5dBV) Single Ended
340mV (-9.5dbV) Balanced
|Output level (Normal)||1.3 Vrms(+2.25dBV) Single Ended
2.6V (+8.25dbV) Balanced
|Frequency Response||20-20KHz +/- 0.25dB|
|THD&IM @ 1KHz (full scale)||<0.03%|
|Output Stage||Active high current, high speed analog amps producing double rate DSD.|
|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 on all inputs as well as raw DSD on I²S inputs, not including the built in Bridge II|
|Input jitter reduction||Effectively 100%, residual immeasurable. No input PLLs, FLLs.|
|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
|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)|