DirectStream Junior
7: (<+06 ®
Owner’s Reference
Owner’s Reference DirectStream Junior
Instructions for Use
DirectStream Junior™
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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Important Safety
Instructions
Owner’s Reference DirectStream Junior
Read these instructions
Heed all warnings
Follow all instructions
WARNING. TO REDUCE THE RISK OF FIRE OR ELECTRICAL SHOCK, DO NOT EXPOSE THIS
APPARATUS TO RAIN OR MOISTURE.
Clean only with a dry cloth.
Do not place flammable material on top of or beneath the component.
All PS Audio components require adequate ventilation at all times during operation. Rack
mounting is acceptable where appropriate.
Do not remove or bypass the ground pin on the end of the AC cord unless absolutely necessary
to reduce hum from ground loops of connected equipment. This may cause RFI (radio frequency
interference) to be induced into your playback setup. All PS products ship with a grounding type
plug. If the provided plug does not fit into your outlet, consult an electrician for replacement of the
obsolete outlet.
Protect the power cord from being walked on or pinched, particularly at plugs, convenience
receptacles, and the point where they exit from the apparatus. Unplug this apparatus during
lightning storms or when unused for long periods of time.
When making connections to this or any other component, make sure all components are off. Turn
off all systems’ power before connecting the PS Audio component to any other component. Make
sure all cable terminations are of the highest quality.
There are no user serviceable fuses inside this product.
THERE ARE NO USER-SERVICEABLE PARTS INSIDE ANY PS AUDIO PRODUCT. REFER ALL
SERVICING TO QUALIFIED SERVICE PERSONNEL
Please contact your authorized dealer, distributor, or PS Audio if you have any questions not
addressed in this reference manual.
PS Audio® is a registered trademark of PS Audio Inc., and is restricted for use by PS Audio, Inc., its
subsidiaries, and authorized agents.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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Thank You
Thank you for your purchase of the PS Audio® DirectStream Junior Digital to Analog Converter.
Designed by Ted
Smith
The PS Audio PerfectWave™ DirectStream Junior Digital to Analog Converter (DAC) is a state ofthe-art DAC, preamplifier and media center. DirectStream accepts PCM as well as DSD Digital Audio
data and converts it to high-performance analog audio that can be fed directly to a power amplifier or
preamplifier.
DirectStream Junior, based on its larger sibling, the DirectStream DAC, represents a major advancement
in the art of recreating the musical event.
Uncover What
You’ve Been
Missing
Musical information that may have previously been hidden (or covered up by other DACs) in digital
audio media ranging from CDs to high resolution downloads will be uncovered by DirectStream Junior.
Unique
Architecture
DirectStream Junior features a unique architecture inside. From its digital inputs to its simple output
stage, DirectStream Junior has been hand written, hand designed and personally voiced by its
designer, Ted Smith, along with PS Audio CEO, Paul McGowan and legendary loudspeaker designer
and founder of Infinity Loudspeaker Systems, Arnie Nudell.
Subtle musical details and cues such as upper harmonics, decay, reverb and room
reflections will no longer be masked by the conversion process from digital to analog. Your
music will sound natural, and you will be able to rediscover much of what you may have
been missing in your digital audio library with the introduction of DirectStream Junior into your system.
DirectStream Junior is based on a FPGA (Field Programmable Gate Array) as its core processor and
no off-the-shelf DAC chips are used in its design.
Less Sensitive to
Jitter
DirectStream Junior is less sensitive to the vagaries of input source types and their level of jitter
than most DACs made. Remarkably low jitter sensitivity is one of the hallmarks of this design and
is accomplished by not using classic edge transition detection techniques on the digital input data.
Instead, a proprietary method of extremely fast sample-and-recognize technology is employed that
reduces dependency on cables, jitter and the quality of the incoming data source.
Once the data from the selected digital audio source has been input to DirectStream Junior, it is
upsampled to ten times the standard DSD rate of 2.8MHz before any processing takes place. After
processing by DirectStream Junior, all input data is converted to double rate DSD (5.6MHz) and output
through a passively filtered solid state analog section.
DSD Based
DirectStream Junior is entirely DSD based, even for PCM inputs. DSD was chosen as the core engine
for this instrument for a number of compelling reasons:
• DSD is simple to convert to analog: just low pass filter it.
• DSD is inherently linear: it’s hard to build a PCM DAC that always takes the same sized step in
the output for any possible unit increment of the representative PCM voltage value. The best PCM
technology for linearity is arguably a resistor ladder, then all steps are at least positive for a positive
change in the input, but making resistors that are accurate to one part in 2^16 is hard and to one part
in 2^20, very hard. DSD doesn’t need anywhere near this level of component matching to achieve its
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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Owner’s Reference DirectStream Junior
excellent results.
• DSD soft clips when overdriven, more like magnetic tape: signals which exceed the nominal full scale
value only get slightly compressed, if at all. With PCM, you either have flat tops which induce extra
energy at the squared off edges or, worse, you can have wrap around, which is very
audible.
• All bits in a DSD stream have the same weight: a single bit error anywhere is barely measurable, let
alone audible. Some bits in PCM carry a lot of weight and would make a very loud pop if changed.
PCM needs more error recovery to keep to a given signal to noise ratio (S/N) with a slightly corrupted
digital signal.
• Ironically, most sanely priced PCM players actually use DAC chips that utilize a sigma-delta modulator
(DSD) to get a DSD-like signal anyway. Similarly, many (most) A/Ds are sigma-delta based. The typical
PCM path is analog -> DSD -> PCM -> disc -> PCM -> DSD -> analog. The DSD path can skip the
conversions to PCM. Those conversions can’t be perfect, and artifacts of the steep anti-aliasing filter
or the reconstruction filter aren’t considered benign by many.
• DirectStream Junior handles the PCM conversion from AES/EBU, S/PDIF, TOSLINK, I2S and USB
without recovering a clock by simply watching for the edges and making decisions about what they
mean in context. The result is that any jitter present on the input is lost entirely in the FPGA.
There is little difference between TOSLINK or I2S because the output clock’s rate only depends on the
long term average rate of the inputs not on any edge or other local feature.
The Heart of
Junior
The heart of DirectStream Junior is the DSD engine itself. Regardless of input format, whether PCM
or DSD, all data are upsampled to 30 bits running at 10 times the standard DSD rate and then back
down again to double rate DSD for noise shaping.
The internal volume control keeps complete precision: every bit in the input affects the output of the
DAC for any volume level. Except for the sigma-delta modulation process itself, there is no rounding,
dither, or other trimming - not to 24 bits, not to 32 bits, not to 48 bits, but rather a full 50. The incoming
PCM signal is 30 bits from the upsampling filter, and the volume control is 20 bits wide, so all 50 bits
of the output are used throughout the sigma-delta conversion, requiring more than 50 bits of precision.
DSD only requires a nominal 20 bit signal to noise ratio. This design utilizes a minimum width of 24
bits with wide filter coefficients and 144dB S/N. Use of full precision everywhere and many guard bits
in the IIR filters and the sigma-delta modulator help maintain our goal of perfecting the audio output.
While some designs may run out of headroom or approach saturation levels, depending on the source
material, the new design opts for an extra top bit everywhere in the digital path coupled with an extra
6dB of head room in the analog path beyond the 6dB of headroom that SACD uses. The top bit keeps
PCM from saturating, even if that PCM was not properly bandwidth limited in the initial recording
process.
The output of the DSD engine is fed directly into the output stage, based on high speed video amplifiers
and a passively filtered solid state output stage.
Most output schemes for DSD modulators are active low pass filters, covering the required
120dB S/N ratio from 10Hz to 220MHz and have a number of design challenges and
problems associated with even the best designs.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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No Active Filtering
Owner’s Reference DirectStream Junior
If the analog processing isn’t linear and doesn’t have a very wide bandwidth it will modulate the high
frequency noise that’s inherent in DSD back into the audio band. That modulation will not result in just
low level noise. In practice it will be aliased back into the audible band with serious sonic consequences.
To maintain low noise and linearity, the design incorporates both high speed symmetrical video amps
and a passive output filter.
Design Challenges The first challenge in such a design is the output switch that generates the final 1’s and 0’s of the
modulator. A very clean switch that hooks up the positive rail with a 1 and the negative rail with a 0 is
essential. If it has too much resistance, if the resistance is different at the positive end than the negative
end, if the resistance changes from time to time, … the result will not be as clean as it needs to be.
For 120dB S/N, the switch resistance has to be quite consistent.
Another design requirement is consistent and fast switching time. If the switch is too slow it won’t keep
up with the 5.6MHz signal used in this instrument. If the switch doesn’t react in consistent times it will
introduce jitter. Use of traditional CMOS gates adds a lot of jitter as do cross-coupled totem-poled
bipolar transistors. Instead, DirectStream Junior relies on high speed differential video amps, which
are essentially class A switches, have their outputs either near the top rail or near the bottom power
supply rail (without ever saturating) and provide a very clean DSD switch.
For the all important low pass filtering requirements, an active filter adds self noise even if it is effectively
lowering incoming noise. A unique and effective solution to this problem is a passive filter.
The theory of operation, the firmware and the complex algorithms needed to execute a design of
this magnitude are daunting in their scale and scope. The actual hardware to run the instrument is,
perhaps, easier to grasp, although no less critical to the perfected performance.
Hardware
Highlights
Listed in this section are the highlights of the hardware, system’s overview and design choices made
to create an instrument of this caliber.
1. DirectStream Junior runs from one master clock designed to subtend all possible combinations of
sub-clocks, from 44.1, 88.2, 48, 96, etc in order to eliminate the need for multiple clocks that cause
errors and problems associated when noise from the unused clock propagates to the desired clock.
2. All sample rates supported are synchronously upsampled to 10x the standard DSD sample rate and
then back down to double rate DSD (2 * 64 * 44.1kHz). There’s no need for other clocks to interpret
the inputs, no matter what their sample rate, because of the instrument’s single clock architecture.
3. The path from the single master clock to its retiming flip-flop path is designed as short as possible
and isolated from all other clocking.
Connection
Impedances
4. Connections between sections of the design have large impedances, not only lots of power supply
isolation, but also, for example, 2k resistors in series with digital signals to slow down the edges and
lessen any noise transfer.
5. Similarly, we run I2C, SPI and other control signals as slowly as they can possibly go without
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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causing problems; we also control their transition times, thus limiting the amount of induced noise and
jitter into the main digital processing area.
6. Outputs of the FPGA use the slowest, lowest drive compatible with their function, keeping noise as
low as possible.
7. We use slower, older technology CMOS when we need CMOS. This choice lowers both noise and
jitter potential.
Balanced
Architecture
8. We use balanced signals when practical; they not only lessen radiation and are less sensitive to
radiation, but they lessen noise in the ground and power rails.
9. We use non-saturation logic so the exact transitions are more predictable. Coming out of saturation
is a statistical process.
Signal Isolation
10. High rate signals (or signals with fast edges) are isolated from control signals and especially each
other. If they have to be fast they are terminated appropriately to help address jitter.
Hand Selected
Parts
11. Jitter is addressed everywhere in the design. Every component choice, every signal connection,
every wire routed on the boards are all hand done to lower noise and pay attention to jitter.
12. 0.1% precision thin film low temperature coefficient resistors are incorporated everywhere in the
audio path; 2% film caps in critical places and 5% film caps elsewhere in the audio path. By using
1/8W resistors or 1/4W resistors where others might use a 1/10W resistor, the temperature coefficient
of the resistors is lowered. For digital bypassing, NP0/C0G, or at worst, X7R MLCCs are used.
13. Low noise techniques are employed such as liberal use of low inductance capacitor bypassing
with a self resonance frequency at the main clock rate to keep noise from ever getting into the voltage
rails in the first place.
14. Digital filtering in general, and the upsampling and noise shaping filters in the sigma-delta modulators
in particular, offer many degrees of freedom for a filter designer. There isn’t a mathematically perfect
filter to use (they all have tradeoffs), so we’ve chosen the filters that sound best in our experience, and
in addition to that, we run everything with as wide of an audio bandwidth as possible.
Double DSD
15. Although design choices might have been made to run everything at single rate DSD (64 *
44100Hz), it was decided instead to run at double rate DSD to have a wider audio band below the
upsampling and noise shaping filters. Noise shaping is how a high rate sampled signal can have more
accuracy in part of the spectrum than the 6dB / bit rule and it is understood that the quantizer in a
sigma-delta modulator can hide a multitude of sins in the noise shaping filter. Our instrument still runs
the noise shaping filter at full precision to get the cleanest DSD signal possible.
16. No shortcuts are ever taken in the Digital Signal Processing (DSP) section of the FPGA. Despite the
fact that DSD is only nominally 20bit S/N, the design uses a minimum width of 24 bits throughout the
device. Where needed, very expensive (in terms of math operations) filters with wide coefficients and
144dB S/N are employed along with many guard bits in the IIR filters and the sigma-delta modulator.
17. Every trace on the PC board is hand routed: even for the digital sections. No autorouting is
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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Owner’s Reference DirectStream Junior
employed so that each trace, each critical path is calculated and designed for lowest noise, jitter and
isolation.
The PerfectWave DirectStream Junior DAC represents a significant departure in the design and
execution of PS Audio’s products. We believe this new instrument will help further our industry, music
and the faithful reproduction of music around the world, at an affordable price.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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Location
Owner’s Reference DirectStream Junior
LOCATION
A good location for DirectStream Junior is in a cabinet or on a shelf at an easily accessible height.
Care should be taken to keep it away from power amplifiers or large potentially hum inducing
products. The IR (infrared) receiver for the remote is located to the left of the volume control knob. A
direct line of sight will help with DirectStream Junior's IR sensor.
DirectStream Junior and the PerfectWave Transport (PWT) or the upcoming DirectStream Transport
(DST) were designed to stack on top of each other if they are not placed on separate shelves. To do
this, remove the feet from the unit you wish to place on top of the stack. Carefully place the top unit
so it rests on the bottom unit. You will note that the bottom of the corners of each PerfectWave piece
is specially designed to mate with the top corners of another PerfectWave.
Digital Inputs
DIGITAL INPUTS
DirectStream Junior offers multiple digital input choices including: The Network Bridge II, XLR (AES/
EBU), RCA and TOSlink (S/PDIF), USB as well as I2S. All inputs, including USB, are capable of
accepting high-definition digital audio signals. The TOSlink input is capable of 96kHz, 24 bit audio
and all other inputs, including the USB, are capable of handling up to 192kHz 24 bit of PCM or DoP
data. The I2S inputs can handle single and double rate DSD directly or DoP. The PS Audio NuWave
Phono A/D Converter is capable of sending pure DSD over I2S, as well the upcoming DirectStream
Transport, which will play pure DSD from SACD sources.
HDMI for I2S
DirectStream Junior uses an HDMI cable to transfer I2S data. This data can only be used with another
compatible component, such as the PerfectWave Memory Player, DirectStream Transport, and
NuWave Phono Converter and will not work in other HDMI equipment, as the I2S format incorporated
does not comply with the HDMI standards. The HDMI connector and cable were chosen to carry
the I2S signal because of their superior high-speed data transmission capabilities for multiple clocks
and data lines. PS Audio publishes its I2S standard and it has been adopted by multiple other
manufacturers as well.
DoP
DoP (DSD over PCM) is a standard allowing single rate DSD to travel over S/PDIF (the RCA, XLR and
Network Bridge digital inputs are S/PDIF compatible) as well as over USB and I2S.
It is not currently possible to send DSD directly over S/PDIF, and the DSD files must first be converted
to DoP standards to travel this route.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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DSD File Types
Owner’s Reference DirectStream Junior
It is possible to send DSD files (without conversion to DoP) over DirectStream Junior's I2S inputs. Most
programs, such as JRiver Media Center and Foobar 2000, will automatically convert DSD files to the
DoP standards on the fly if the appropriate checkbox has been enabled. There are no sonic penalties
for conversion to DoP as the raw DSD data is unaffected by the process.
• Carefully unpack the unit. Use the included cotton gloves to remove the unit and place in the chosen
location.
• The piano black top cover has a protective plastic film. Remove this film.
• Connect DirectStream Junior to your digital sources using the appropriate connections.
• Connect the AC cable into the receptacle in back and plug the unit into your Power Plant or into the
wall.
Warranty
Registration
PS Audio products come from the factory with a 3-year warranty. Please register your new DirectStream
Junior. Registration takes just a few minutes, helps us inform you about future upgrades, keeps track of
your serial number and allows us to maintain the highest standards of product quality of any company.
To register your new unit, look on the back panel of DirectStream Junior and note the serial number.
Using any web browser, go to www.psaudio.com and click on My PS. From there you can click on
Register Products.
Once you have completed the registration process you can then go to the PS website and look at
the My Registered Products page. The link to this page is located at the top right hand corner of the
website once you are logged in. If you do not have web access you may register the unit via mail or
phone. Notification of software upgrades to this product will be available only to registered owners via
the web and email.
Connecting Digital
Sources
Connecting
Through Ethernet
CONNECTING TO A DIGITAL SOURCE
There are four methods of connecting the digital inputs of DirectStream Junior: Through the home
network, S/PDIF, USB and I2S. The home network option requires the use of a router, CAT5 Ethernet
cable, NAS or computer with the appropriate program installed (like JRiver), and a controller. S/PDIF
is a serial digital interface available as an optical source (TOSlink), coaxial source (RCA) or balanced
source (AES/EBU XLR). Connect to your digital sources with any of these three cable types.
Direct to
Computer
USB is the preferred method of connection for a direct-to-computer connection and DirectStream
Junior is capable of processing up to 352kHz 24 bit PCM data as well as both single and double rate
DSD converted to DoP. Connect DirectStream Junior to your computer using a well regarded USB
cable and make sure to set the output of your computer to the higher 192kHz 24 bit standard. Once
connected, your computer should automatically install DirectStream Junior as a new device if you
have a Mac. If you have a Windows operating system, you may need to download the appropriate
driver from our website and install it on your computer. The driver for DirectStream Junior is the same
as that used with DirectStream, the PWD and NuWave DSD.
Driver Conflicts
If the device is not recognized or you are unable to obtain output through DirectStream Junior, it is
possible there is a driver conflict on your computer. Please see the Troubleshooting section for further
assistance on playback issues via USB.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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I2S Sources
Owner’s Reference DirectStream Junior
I2S is available through several manufacturers as well PS Audio equipment such as the PerfectWave
Transport, NuWave Phono A/D Converter, and DirectStream Transport. I2S is a parallel data connection
with separate clocks and data and transferred via an HDMI cable. I2S will typically provide a slightly
better performance standard than any serial data stream such as S/PDIF or AES/EBU.
You can connect one or all six inputs at the same time. For instance, you can connect the USB input to
your computer and the coax input to your CD player. Then you can simply choose which one to listen
to from the front selector button, the remote, or set inputs to AUTO.
If you are using USB, make sure both the computer and DirectStream Junior are connected and
powered up. USB also requires a driver to operate properly. Mac computers running OSX have the
driver built in. Windows based computers require the PS Audio driver to be installed. Download the
driver from our website; it is the same driver used in the PWD, DirectStream, and NuWave Phono
Converter.
DirectStream Junior will show up under Device Manager as PS Audio PerfectWave DSD, under a
heading PS Audio USB 2.0 Audio Devices.
Connecting the
Output
CONNECTING DIRECTSTREAM JUNIOR'S OUTPUT
DirectStream Junior is designed to drive a power amplifier directly, or as another input on a preamplifier.
The outputs of DirectStream Junior are high-performance, high current outputs that can drive long
lengths of interconnect cable without degradation.
RCA and XLR
DirectStream Junior has two types of analog outputs: balanced XLR or single ended RCA. It is fine
to use both outputs at the same time. Be aware that most amplifiers and preamplifiers will produce
6dB higher level with the balanced outputs relative to the single ended outputs. If you are using both
outputs be advised they will be at different levels. Our preference for connection to a power amplifier
or preamplifier is through the balanced XLR outputs of DirectStream Junior.
Output Level
Setting
If DirectStream Junior has a gain mismatch with your power amplifier, you can use the balanced outputs
and achieve 6dB more gain or choose the single ended RCA outputs for lower gain. DirectStream
Junior also has two output levels available to users.
Use the Gain button on the remote or go to the setup menu on the front panel display to select the
best output level. To access the setup menu, press the front panel selector button to the left of the
display for 3 seconds. Step through the menu options by pressing the button once for each menu.
Attenuator IN is the lowest volume setting, Attenuator OUT is the highest level setting.
RCA or single ended inputs will be the typical inputs, as many preamplifiers, surround processors,
receivers, integrated amplifiers and power amplifiers have only this standard type of input.
Plug either the RCA or the XLR outputs of DirectStream Junior into a line level input on the preamp,
integrated, amplifier or subwoofer. Do NOT plug the output of DirectStream Junior into a phono or
equalized input of any type.
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PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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Use Only High
Quality Power
Cables
Owner’s Reference DirectStream Junior
Once everything has been connected, use a high quality AC cable to power DirectStream Junior.
DACs in particular are quite sensitive to AC power and produce a bit of line noise themselves. Make
sure you have a high quality shielded power cable to power DirectStream Junior, and a Power Plant
AC Regenerator if possible.
PS Audio produces an entire line of high quality quiet power cables that are generally accepted as
being some of the best in the industry. Whatever you choose, make sure it honors the music.
Rear Panel Power
Switch
Turn the AC power switch in the rear of DirectStream Junior to the ON position. The power switch is
located to the left of the AC inlet as you face the rear panel.
As soon as the switch is activated, the front panel display will show the initializing information. This
screen shows when DirectStream Junior’s internal “engine” is being loaded with the firmware that runs
DirectStream Junior.
After the initializing screen, you will see the volume control setting.
Front Panel
Standby Button
The front panel PS logo button, located on the upper left hand corner of the unit, is the Ready/
Operation Mode control for DirectStream Junior. This control has two modes: Ready Mode and
Operational Mode. Ready Mode (Standby) is designed to keep power on to critical internal circuitry,
including power supply capacitors, thermally sensitive semiconductors and integrated circuits.
Press this front panel logo button to activate the Ready Mode or to place DirectStream Junior in
Operational Mode. When pressed to enter Ready Mode, the display, as well as the outputs are turned
off, but all the unit’s critical internal circuitry remains active.
Keep Power On
If you wish to conserve energy consumed by DirectStream Junior, it will be necessary to use the rear
panel power switch. Using this rear panel switch will remove power from critical components and in
order to gain maximum performance levels you will need to turn DirectStream Junior’s power on at
least 3 hours before use. DirectStream Junior is designed to be left powered on at all times.
Should DirectStream Junior need to be rebooted, use the rear panel power switch to power cycle the
instrument. It's best to wait 30 seconds before powering back on.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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Select the Input
SELECT THE INPUT
The first step is to select the input you wish to play. This can be accomplished with the remote control
or through the front panel selector and display.
Touch the selector button on the left side of the screen. The first press will show the active display.
Touch again and you toggle to the next input.
Lock Light
Each input has a lock light associated with it. The lock light has two states: connected (displays an
asterisk in the upper right corner of the display) and not connected (nothing displayed). It is also
possible to select AUTO. AUTO input senses when a digital input is actively playing music and switches
to the live input. This is the recommended input setting.
Name the Input
INPUT NAMING
For greater convenience, it is possible to assign a custom name to each input, such as PWT, XLR, etc.
To name each input, you must first enter the setup display. Select the input you wish to change. Once
selected, hold the selector button down for 3 seconds to enter the display mode. The first screen is
balance. Press the selector button once again, while in the setup mode, to toggle to the input naming
screen. The input already selected will appear, along with data and bit rate information. Depress and
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hold the selector button until the Name Edit Screen is displayed.
The cursor sits under the letter you can select. Rotate the volume knob to choose which letter you
desire. Press the selector button and that letter will appear as part of the name. Repeat the process
until you spell the input name. Press and hold the selector button to leave the naming edit screen.
Set the Output
Level
DirectStream Junior has two output levels: High and Low. In the standard output mode, DirectStream
Junior will provide adequate output level to directly feed a power amplifier without use of a preamplifier.
If the power amplifier or preamplifier is overly sensitive, or you need to reduce the output level of
DirectStream Junior for any reason, you can activate the output attenuator to reach a lower level.
There should be no sonic penalty for doing so.
To turn on/off the output attenuator, press the DAC Level button on the remote. Or, go to the setup
screen which is accessed by depressing the selector button, located to the left side of the display, for 3
seconds to enter the setup mode. Toggle through the setup screens with a button push. Once you get
to the Attenuator screen, use the volume control knob to select In (lowest gain) or Out (normal gain).
Screen Brightness
The unit’s screen brightness can be adjusted in the setup menu as well. The display can be turned
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off by pressing the button labeled “DIM” located on the remote. When you are in the DIM mode, the
screen will come back on when you turn the volume control knob or press a remote key. To turn the
DIM feature off, press “ON.” You can also adjust brightness in the setup menu.
Screen On-Time
You can also adjust the length of time the display remains visible, from 10 seconds to 1 hour, or select
AUTO. AUTO will activate the display when any changes occur, like a new volume setting or input
change. It will go dark when no music is playing. When music begins, the display will automatically
display the volume setting.
Network Bridge
DirectStream Junior can become far more than a high-performance stereo DAC with its built-in
Network Bridge II that connects to any home network. The Bridge II allows playback from a source not
directly connected to DirectStream Junior using a UPnP protocol and separately available controller
and server, such as a NAS.
The Network Bridge II incorporates the exact same Digital Lens™ technology found in the PWT –
without the input to the Lens being from a nearby source. Instead, the input to the internal Lens of the
Bridge II is over a network: addressable through an Ethernet connection. Music stored on a hard drive
or even an internet radio service are all accessible via the Network Bridge II.
Bridge Operation
BRIDGE II OPERATION
The PS Audio Network Bridge II is built into DirectStream Junior. The Bridge provides network
connectivity to a media server or NAS. The Network Bridge is a UPnP compatible device, requiring a
UPnP server and controller to stream to the Bridge. A program like JRiver Media Center, available on
both Mac and Windows platforms, can be configured to act as both a UPnP server and Controller.
Many NAS come with UPnP servers built into their operating systems. If you use a NAS, you will
control the NAS and Bridge through the use of a UPnP controller, typically via a mobile device, such
as a tablet or phone, that have a UPnP compatible controller app, such as PlugPlayer, or MConnect.
To use the Bridge, the rear panel Ethernet connector must be plugged into your home router through a
CAT5 Ethernet cable. A WIFI Ethernet Bridge can be used, but is not recommended. Once connected,
the Bridge should be visible on the network to a controller that is also on the home network via WIFI or
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hard wired through CAT 5. Select the PS Audio Bridge, or whatever friendly name you have set for the
Bridge, to connect the UPnP server. Once connected, change DirectStream Junior’s input to Input 7,
labeled the same as the Bridge friendly name. You should now be able to stream music to the Bridge.
Using JRiver
If you are using JRiver Media Center, it will be necessary to turn JRiver’s DLNA/UPnP server on to
recognize the Bridge. Make sure the computer running JRiver Media Center is connected to the
same router/home network as the PS Audio Network Bridge. In JRiver, go to Tools->Options->Media
Network and check mark the box that reads: Use media network to share this library and enable
DLNA.
Follow instructions and once setup, the Bridge should appear in the JRiver Media Center far left
window under Playing Now. Select the Bridge and you should be connected.
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Using a NAS
Owner’s Reference DirectStream Junior
If you are using a NAS and mobile controller, the Bridge should be visible on the controller app’s connect
screen. The image shows MController (from MConnect) and the screen you go to for connection to the
Bridge. In this case, the Bridge friendly name has been set, as GoldBridgeII. There is another, second
Bridge in this image, labeled SR1.
To select the NAS or UPnP server of any type, in MController, touch the lower icon that says Browser.
Choose the server you wish to connect to, or VTuner, for internet radio access.
MConnect’s MController app is our recommended mobile platform UPnP controller and is available for
both Android and Apple tablets and phones.
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Changing Bridge
Friendly Name
CHANGING THE FRIENDLY NAME
Many times it is less confusing to change the standard Bridge name from its default of Bridge II to
another, more familiar name, like John’s DAC. This friendly name is what will appear in the JRiver or
MController Play-To windows as described above. To change the friendly name, you must access
DirectStream Junior’s setup window. Press and hold the front panel selector button (next to the display
on the lefthand side) for 3 seconds to access the setup menu. Press the selector button to toggle to
the next setup screen. Press the button 6 times to access the friendly name screen. To change the
name, press and hold the selector button for 3 seconds while in the friendly name screen. The edit
menu appears. Follow the same instructions found in the Input Naming section of this manual for
further instructions.
Network Settings
NETWORK SETTINGS
It is sometimes useful to find out the network setting when you have the Network Bridge connected
to your home network through the router. To discover the network setting, go to the setup menu by
pressing and holding the front panel selector button for 3 seconds. Toggle through the screens by
multiple button presses until you arrive at the Network Setting screen.
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Bridge Updates
Owner’s Reference DirectStream Junior
BRIDGE UPDATES
From time to time, the Network Bridge will receive firmware updates when available. The update
notifications can be accessed over the internet if the Network Bridge is properly connected to the
home network router, which must itself be connected to the internet.
To find out if there is an update available, go to the setup menu. Press and hold the selector button for
3 seconds, then toggle to the Bridge Update screen with multiple selector button pushes.
Junior’s OS
Updates
UPDATE DIRECTSTREAM JUNIOR’S OPERATING SYSTEM
DirectStream Junior operates from sophisticated software that is built in to the device, but upgradable
by the user through the rear panel mounted USB connector. To check for the current firmware version,
simply hold the selector button next to the display for 3 seconds to enter the setup scroll to the Version
screen.
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When New
Firmware is
Available
Owner’s Reference DirectStream Junior
When a new operating system become available, it may be obtained by ordering a pre-programmed
USB memory stick directly from PS Audio, or downloaded to your own USB memory stick for free from
the PS Audio website. To install, place the USB stick in the rear of DirectStream Junior. Then, turn off
the rear panel power switch. Wait for 10 seconds, then turn the rear panel main power switch to the
on position, rebooting the instrument. The front panel Ready Light will begin blinking, signifying the
new firmware is being installed.
DO NOT REMOVE THE POWER OR DO ANYTHING WHILE THE UPDATE PROCESS IS TAKING
PLACE. BE PATIENT AND WAIT UNTIL THE LOGO LIGHT BLINKING IS DONE.
Once the blinking has finished, keep the power to the unit on until it has fully initialized and is ready for
operation again. Remove the USB memory stick.
DirectStream Junior does need some care and is appreciative of being fed proper AC power. A Power
Plant AC regenerator is recommended for this task.
Should minor scratches occur in your top cover, simply purchase any type of high quality automotive
scratch removal polish such as Kit’s Scratch Out or McGuire’s products. Car finish polish and wax can
both be used on this surface for a beautiful luster.
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PH: 720.406.8946 [email protected] www.psaudio.com
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©2016 PS Audio Inc. All rights reserved.
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No Sound
If no sound comes out of the system with DirectStream Junior connected, there are several areas to
check. Either you are not getting an audio signal into the preamplifier, or you don’t have a good digital
source feeding DirectStream Junior.
First, check to make sure your preamp, integrated, receiver or amplifier is switched to the same input
DirectStream Junior is connected to. Test the connection and the cables to make sure. Keeping the
input selected and using the same cable, connect this input to a known good source like a tuner or
the direct analog output of a CD player. If that works, then it is most likely not a connection problem
between DirectStream Junior and the preamp, integrated or amplifier.
The next step is to check and see if the digital input is properly connected. Look on the front panel of
DirectStream Junior to see if the locked light is illuminated. If it is not, this is most likely the problem.
You can troubleshoot this by making sure DirectStream Junior is on the proper input and that you have
connected the input correctly. If this fails, try replacing the digital interconnect or try using another
type. For instance, if you are using a coax connection, try using the CD player’s optical output instead
or try replacing the cable.
USB Problems
USB – DirectStream Junior not recognized, or no sound via USB
To play music from your computer into the DirectStream Junior via USB, you must have a driver installed that
communicates with DirectStream Junior. On a Mac computer with OS X Yosemite, the drivers are already
available and the unit should be automatically recognized. You can then go and choose the PS Audio USB
driver to play to by going to System Preferences->Sound and select the PS Audio PerfectWave DSD.
You can also go to Applications->Utilities->Audio Midi and select the driver as well as set the sample rate.
Currently, Windows operating systems do not come with the appropriate USB audio driver software
installed. You will need to download the PS Audio USB driver from the PS Audio website. You can
also contact our support staff via email ([email protected]) or phone (+17204068946), or simply
go to www.psaudio.com and click on Resources, then click on the Downloads page. You must then
unzip the driver and install it on your Windows machine. Once installed, Windows will recognize
DirectStream Junior and allow you to select it for playback from any program on your computer.
If you are still unable to obtain sound via USB on a Windows based device, it is most likely the result
of a partial or incorrect driver installation.
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It May Be a Driver
Conflict
You may have also experienced a pop-up window asking you to provide the correct driver. In any of
these cases, the remedy is quite simple. Remove the device and force Windows to reinstall the driver
and the device.
DirectStream Junior will show up under device manager as “PS Audio PerfectWave DSD” It should
show up under a heading “PS Audio USB 2.0 Audio Devices”, this is the USB2.0 driver.
The entry under “Sound video and game controllers” is the USB1.0 fallback driver.
Bridge Connection CAN’T CONNECT TO THE BRIDGE
Most problems with the Network Bridge trace back to home networks and their routers. Make sure
Issues
you have a modern, high speed router and connection to the Bridge is through CAT5 network cable,
not WIFI.
Make certain the server, computer, and mobile device are on the same network as the Bridge. We
often see this problem arise, especially with WIFI connected mobile devices. The mobile device may
not be sharing the same network, through WIFI, as the home router. If you are using a mobile device,
such as a phone or tablet to control the server, make sure the mobile device has WIFI enabled and is
on the same network as the Bridge.
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PH: 720.406.8946 [email protected] www.psaudio.com
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The server must be UPnP compatible. Programs like iTunes are not UPnP compatible and cannot
stream over a home network. iTunes and non-UPnP compatible servers must be connected to
DirectStream Junior through USB to work.
JRiver Problems
JRiver problems are common. If the Bridge is not displayed as an option to select, look under Tools>Options->Media Network and check mark the box that reads: Use media network to share this
library and enable DLNA.
Follow instructions and once setup, the Bridge should appear in the JRiver Media Center far left
window under Playing Now. Select the Bridge, and you should be connected.
Check the Logo
THE UNIT DOES NOT APPEAR TO POWER ON
It may be in Standby mode. Verify that the rear panel master power switch is in the UP/ON position.
Press the front panel PS logo button on the upper left side of the front panel to take the unit out of
standby.
If You Have Hum
If you experience a hum through the speakers, this can be caused by several things. The first is the
source. If there is an excessive amount of buzz or noise from the loudspeaker, it may be caused by
a ground loop, a light dimmer in the home, poor AC power, or any number of causes. The quickest
way to determine where to start your search is to simply turn the preamplifier, integrated, receiver or
amplifier off, disconnect the audio cables between it and DirectStream Junior, and see if the hum goes
away when you turn the preamplifier, integrated, receiver or amplifier back on. If it does, it’s most likely
a ground loop or buzz from a dimmer.
If this doesn’t solve the problem, reconnect DirectStream Junior and follow these easy humbusting
tips.
Ground Loops
The easiest way to figure out where ground loop problems lie is by the process of elimination. You
need to determine where the hum or buzz is coming from within your system.
If the hum/buzz goes away when you remove the inputs to the power amp, your next step will be
to reconnect the amp and move further down the chain. If you have a preamp, or processor that
is feeding the power amp, your next step would be to disconnect all inputs to the preamplifier or
processor. Once these are disconnected, and the preamp or processor is connected only to the
power amplifier, turn the system on and again, listen for hum. Should the hum now appear, it is a
problem with your preamp, processor, DAC or their interaction with the power amp. Before returning
the preamp, processor or DAC to the manufacturer, try a cheater plug to break a ground loop. Cheater
plugs are simple devices that convert a three prong AC plug into a two prong AC plug and in the act
of converting three prongs to two prongs, they disconnect the ground from the wall socket. Try one of
these on the preamp, or the power amp, or both.
If you determine that there is still no hum present when the preamp, processor, or DAC is connected
with no inputs, then selectively begin plugging in your various inputs one at a time. After each
connection, check for hum until you discover the humming culprit.
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VCRs, surround processors, and any device that is connected to a television cable or satellite dish can
cause a loud buzz and should always be suspect. If, by the process of elimination described above,
you determine it is a component like a VCR that is causing the hum/buzz to occur, and using a cheater
plug doesn’t help matters, it may be necessary to isolate the cable connection (CATV) with an isolation
transformer. This inexpensive device is available at most Walmart, Radio Shack or department store
type outlets and is sometimes called a ‘matching transformer’. If you have problems finding one, call
your local cable TV company for advice. The matching transformer will be placed between the cable
TV cord and the VCR, TV or processor.
Just remember, take the system down to its simplest level of connection. Find a way to hook the
system up with as many pieces of the system missing or not connected. Keep it simple and get it
to the point where the hum’s gone. Then start adding back components one at a time until the hum
returns.
Finding the problem is 9/10ths of the work in finding a solution.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio International Inc. All rights reserved.
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Limited Three Year Warranty
Should I Register My Product?
•
•
•
•
•
Registering your product validates the warranty start date.
If you do not register your product within 30 days of service, a copy of your purchase receipt from an authorized PS
Audio dealer may be used as a proof of purchase to establish the warranty start date.
If no proof of purchase from an authorized PS Audio dealer or registration is provided, the production date of the
product will be used to determine the warranty start date.
Registration can be completed online, by phone, by mail, or by email.
You may wish to sign up for PS Audio’s monthly newsletters, specials, product updates, and/or Paul’s Daily Posts.
What Does this Warranty Cover?
This warranty covers defects in material and workmanship for products purchased from PS Audio or its authorized dealers
and agents.
What Will PS Audio Do to Correct the Problem?
In the event your product fails your sole remedy under this limited warranty shall be to return the product to PS Audio or an
authorized PS Audio repair center. The product will be repaired without charge for parts or labor, replaced, or the purchase
price refunded through the original point of purchase, at the option of PS Audio.
What is the Period of Coverage?
This limited warranty is in effect for 3 years from the date the unit was first purchased from PS Audio or its dealers and
agents.
Who Pays for Shipping?
You are responsible to pay for the safe and proper shipment of the warrantied product to PS Audio or its authorized repair
center.
PS Audio or it’s authorized repair center will pay the cost of returning the repaired or replacement product to you under this
warranty.
What Does this Warranty Not Co ver?
•
•
•
•
•
•
This warranty does not cover damage due to:Accidents, carelessness, improper transportation, misuse, neglect, or
abuse
Failure to follow the operating instructions that are provided by PS Audio in the owner’s manuals (available for
download at psaudio.com)
Use in any manner inconsistent with PS Audio’s operating instructions (available for download at psaudio.com)
Lack of routine maintenance
Connection to an improper voltage supply
Alterations or modifications to the unit
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©2016 PS Audio Inc. All rights reserved.
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•
•
•
•
®
Owner’s Reference DirectStream Junior
Improper or unauthorized repair, including repairs not authorized by PS Audio or a PS Audio authorized repair
center
Fire, lightning, flood, “acts of God,” or other contingencies beyond the control of PS Audio
Products purchased through an unauthorized source (if you have questions as to whether or not a dealer is
authorized, please contact customer support at psaudio.com)
Products with a factory-applied serial number that has in any way been altered, defaced, or removed
Limitations on PS Audio’s Obligations Under this Warranty
•
•
•
•
In no event will PS Audio’s liability to you exceed the original purchase price of the unit.
This warranty does not cover the cost of custom installation, customer instruction, setup adjustments, or signal
reception problems.
This warranty does not cover consequential and incidental damages. Some states do not allow the exclusion or
limitation of incidental or consequential damages, so the above limitation or exclusion may not apply to you.
In the event your warrantied product cannot be repaired, PS Audio will replace or refund the unit. We reserve
the right to replace any out-of-stock, discontinued, or limited edition products with a comparable product.
Discontinued products may not be available for warranty replacement.
How Can the Warranty be Transferred?
This warranty is for the benefit of the original purchaser of the product. The warranty may be transferred to a subsequent
purchaser during the 3 year warranty period. To do this, you must contact PS Audio directly to set up transfer of
registration.
How Do I Get Warranty Service?
To locate an authorized PS Audio repair center, for service assistance, or for help with the operation of a product or just
for information, please contact PS Audio customer support.
Warranty Service Within the US
•
•
•
•
•
•
You must first obtain a Return Merchandise Authorization Number (RMA#) to receive warranty service and prior to
returning any item. Contact PS Audio or an authorized PS Audio repair center to receive an RMA#.
You must put the RMA# on all returns. If it is not clearly marked, PS Audio will return the package back to you,
freight collect.
You should include a description of the problem, along with the RMA# inside the packaging.
Original packaging should be used for the safe transit of your PS Audio unit to the repair center. If you do not
have the original packing, PS Audio can sell and ship to you replacement packaging.
You are responsible for the cost of shipping the product to a PS Audio authorized repair center. You should insure
the product for its full retail cost in the event it gets lost or damaged in transit. PS Audio is not responsible for
damage incurred in products sent to us.
Shipping your product in non-PS Audio packaging may void this warranty. PS Audio reserves the right to charge
you for new factory packaging to return your product after a repair.
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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How State Law Applies
This warranty gives you specific legal rights, and you may also have other rights which vary from state to state.
Warranty Service Outside of the US
PS Audio has authorized distribution in many countries of the world. In each country, the authorized importing
distributor has accepted the responsibility for warranty of products sold by that distributor. Warranty service should
be obtained where the product was purchased.
Changes to Our Products
PS Audio reserves the right to modify the design of any product without obligation to purchasers of previously
manufactured products and to change the prices or specifications of any products without notice or obligation to
any person.
PS Audio Inc.
4826 Sterling Dr.
Boulder, CO 80301
Phone - 720.406.8946
Fax - 720.406.8967
Email - [email protected]
Web - psaudio.com
4826 Sterling Drive, Boulder, CO 80301
PH: 720.406.8946 [email protected] www.psaudio.com
©2016 PS Audio Inc. All rights reserved.
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