PS Audio DirectStream Junior Owner's Reference Manual

®

Instructions for use

Owner’s Reference

Owner’s Reference DirectStream Junior

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

DirectStream Junior

™

Introduction

®

Important Safety
Instructions

Owner’s Reference DirectStream Junior

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 ammable 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 t into your outlet, consult an electrician for replacement of the
obsolete outlet.

Read these instructions

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
Inc., its subsidiaries, and authorized agents.

®

is a registered trademark of PS Audio Inc., and is restricted for use by PS Audio,

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Introduction

®

Thank you

Designed by Ted
Smith

Uncover what
you’ve been
missing

Owner’s Reference DirectStream Junior

Thank you for your purchase of the PS Audio® DirectStream Junior Digital To Analog Converter.

The PS Audio PerfectWave™ DirectStream Junior Digital to Analog Converter (DAC) is a state
of-the-art DAC, preamplier 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
amplier or preamplier.

DirectStream Junior, based on its larger sibling, DirectStream DAC, represents a major advancement
in the art of recreating the musical event.

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.

Subtle musical details and cues such as upper harmonics, decay, reverb and room
reections 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.

Unique
architecture

Less sensitive to
jitter

DSD Based

DirectStream Junior features a unique architecture inside. From its digital inputs to its simple output
stage, DirectStream 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 Innity Loudspeaker Systems, Arnie Nudell.

DirectStream Junior is based on a FPGA (Field Programmable Gate Array) as its core processor
and no o-the-shelf DAC chips are used in its design.

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 used 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 ltered solid state analog section.

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 lter 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

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Introduction

®

positive change in the input, but making resistors that are accurate to one part in 216 is hard and
to one part in 220 very hard. DSD doesn’t need anywhere near this level of component matching
to achieve its 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  at tops which induce
extra energy at the squared o 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 lter or the reconstruction lter 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 dierence 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.

Owner’s Reference DirectStream Junior

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 aects 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 lter 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 lter coecients and 144dB S/N. Use of full precision everywhere
and many guard bits in the IIR lters 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
ampliers and a passively ltered solid state output stage.

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Introduction

®

No active ltering

Design
challenges

Owner’s Reference DirectStream Junior

Most output schemes for DSD modulators are active low pass lters, 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.

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 lter.

The rst challenge in such a design is the output switch that generates the nal 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 dierent 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 dierential
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.

Hardware
Highlights

For the all important low pass ltering requirements an active lter adds self noise even if it is
eectively lowering incoming noise. A unique and eective solution to this problem is a passive
lter.

The theory of operation, the rmware 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.

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.

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Introduction

Connection
impedances

Balanced
architecture

®

3. The path from the single master clock to its retiming ip-op path is designed as short as
possible and isolated from all other clocking.

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
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.

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.

Owner’s Reference DirectStream Junior

Signal isolation

Hand selected
parts

Double DSD

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.

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 lm low temperature coecient resistors are incorporated everywhere in
the audio path. 2% lm caps in critical places and 5% lm 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
coecient of the resistors are 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 rst place.

14. Digital ltering in general, and the upsampling and noise shaping lters in the sigma­delta modulators in particular, oer many degrees of freedom for a lter designer. There isn’t
a mathematically perfect lter to use (they all have tradeos), so we’ve chosen the lters that
sound best in our experience and in addition to that we run everything with as wide of an audio
bandwidth as possible.

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 lters. Noise shaping is how a high rate sampled signal can have

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Introduction

®

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 lter. Our instrument
still runs the noise shaping lter 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) lters with
wide coecients and 144dB S/N are employed along with many guard bits in the IIR lters and
the sigma-delta modulator.

17. Every trace on the PC board is hand routed: even for the digital sections. No autorouting is
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 signicant 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 aordable price.

Owner’s Reference DirectStream Junior

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started

®

Owner’s Reference DirectStream Junior

Location

Digital Inputs

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 ampliers 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

DirectStream Junior oers 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-denition 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 I

DOP

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

2

S

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 (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)

©2016 PS Audio Inc. All rights reserved.

Getting Started viii

Getting Started

®

Owner’s Reference DirectStream Junior

as well as over USB and I2S.

It is not currently possible to send DSD directly over S/PDIF and the DSD les
must rst be converted to DoP standards to travel this route.

DSD le types

Warranty
Registration

It is possible to send DSD les (without conversion to DoP) over DirectStream's
I2S inputs. Most programs, such as JRiver Media Center and Foobar 2000, will
automatically convert DSD les to the DoP standards on the y if the appropriate
checkbox has been enabled. There are no sonic penalties for conversion to DoP
as the raw DSD data is unaected 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 lm. Remove this lm.

• 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.

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
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. Notication
of software upgrades to this product will be available only to registered owners
via the web and email.

Connecting
digital sources

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

CONNECTING TO A DIGITAL SOURCE

There are four methods of connecting the digital inputs of DirectStream: Through
the home network, S/PDIF, USB and I

©2016 PS Audio Inc. All rights reserved.

2

S. The home network option requires the use

Getting Started ix

Getting Started

®

Owner’s Reference DirectStream Junior

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started x

Getting Started

®

Owner’s Reference DirectStream Junior

Connecting
through Ethernet

Direct to
Computer

Driver conicts

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.

USB is the preferred method of connection for a direct-to-computer connection
and DirectStream Junior is capable of processing up to 192kHz 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.

If the device is not recognized or you are unable to obtain output through
DirectStream Junior it is possible there is a driver conict on your computer.
Please see the Troubleshooting section for further assistance on playback issues
via USB.

2

S sources

I

2

I

S 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.

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started xi

Getting Started

®

Owner’s Reference DirectStream Junior

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

RCA and XLR

Output level
setting

CONNECTING DIRECTSTREAM JUNIOR'S OUTPUT

DirectStream Junior is designed to drive a power amplier directly, or as another
input on a preamplier. The outputs of DirectStream are high-performance,
high current outputs that can drive long lengths of interconnect cable without
degradation.

DirectStream Junior has two types of analog outputs, balanced XLR or single
ended RCA. It is ne to use both outputs at the same time. Be aware that most
ampliers and preampliers 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 dierent levels. Our preference for connection to a power
amplier or preamplier is through the balanced XLR outputs of DirectStream
Junior.

If DirectStream Junior has a gain mismatch with your power amplier, 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 preampliers,
surround processors receivers, integrated ampliers and power ampliers 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, amplier or subwoofer. Do NOT plug the output
of DirectStream Junior into a phono or equalized input of any type.

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

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started xii

Getting Started

®

Owner’s Reference DirectStream Junior

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.

Use only high
quality power
cables

Rear panel power
switch

Front panel
standby button

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.

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 rmware that runs DirectStream Junior.

After the initializing screen, you will see the volume control setting.

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 o, but all the unit’s critical internal
circuitry remains active.

Keep power on

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

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.

©2016 PS Audio Inc. All rights reserved.

Getting Started xiii

Getting Started

®

Owner’s Reference DirectStream Junior

Select the input

Lock light

SELECT THE INPUT

The rst 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 selector button to the left of the screen. The rst press will show the active
display. Touch again and you toggle to the next input.

Each input has a lock light associated with it. The lock light has two states:
connected (displays an asterisks 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

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

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 rst enter the setup display.

©2016 PS Audio Inc. All rights reserved.

Getting Started xiv

Getting Started

®

Owner’s Reference DirectStream Junior

Select the input you wish to change. Once selected, hold the selector button
down for 3 seconds to enter the display mode. The rst 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 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 amplier without use of a preamplier. If the power amplier, or preamplier,
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/o 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).

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started xv

Screen
brightness

Getting Started

®

Owner’s Reference DirectStream Junior

The unit’s screen brightness can be adjusted in the setup menu as well. The
display can be turned o 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 o,

press “ON.” You can also adjust brightness in the setup menu.

Screen on-time

Network Bridge

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

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.

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

©2016 PS Audio Inc. All rights reserved.

Getting Started xvi

Getting Started

®

Owner’s Reference 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

Using JRiver

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 congured 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 hard
wired through CAT 5. Select the PS Audio Bridge, or whatever friendly name you

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started xvii

Getting Started

®

Owner’s Reference DirectStream Junior

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.

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.

Using a NAS

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.

Changing Bridge
Friendly Name

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

Changing the Friendly Name

Many times it is less confusing to change the standard Bridge name from its default

©2016 PS Audio Inc. All rights reserved.

Getting Started xviii

Getting Started

®

Owner’s Reference DirectStream Junior

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 for 3 seconds to access
the setup menu. Press the selector button (next to the display) to toggle to the
next setup screen. Press the button 6 times to access the friendly name screen.

Network settings

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

It is sometimes useful to nd 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

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started xix

Getting Started

®

Owner’s Reference DirectStream Junior

presses until you arrive at the Network Setting screen.

Bridge Updates

Bridge Updates

From time to time the Network Bridge will receive rmware updates when available.
The update notications 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 nd 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

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

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 rmware version simply hold the selector button next to

©2016 PS Audio Inc. All rights reserved.

Getting Started xx

Getting Started

®

Owner’s Reference DirectStream Junior

the display for 3 seconds to enter the setup scroll to the Version screen.

When new
rmware is
available

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 o 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 rmware 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 nished, 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 nish polish and wax can both be used on this surface for a beautiful
luster.

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started xxi

Getting Started

®

Owner’s Reference DirectStream Junior

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Getting Started xxii

Troubleshooting

®

Owner’s Reference DirectStream Junior

No sound

USB Problems

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 preamplier,
or you don’t have a good digital source feeding DirectStream Junior.

First, check to make sure your preamp, integrated, receiver or Amplier 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 amplier.

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 – 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. 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 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 sta via
email ([e-mail]) or phone, ([phone]) or simply go to www.
psaudio.com and click on the Downloads page. You must then unzip the driver
and install it on your Windows machine. Once installed, Windows will recognize
DirectStream and allow you to select it for playback from any program on your

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

Troubleshooting xxiii

©2016 PS Audio International Inc. All rights reserved.

Troubleshooting

®

Owner’s Reference DirectStream Junior

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.

It may be a driver
conict

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.

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio International Inc. All rights reserved.

Troubleshooting xxiv

Troubleshooting

®

Owner’s Reference DirectStream Junior

Bridge
connection
issues

JRiver problems

Can’t connect to Bridge

Most problems with the Network Bridge trace back to home networks and their
routers. Make sure you have a modern, high speed router and connection to the
Bridge is through CAT5 network cable, not WIFI.

Make certain the server, computer, 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.

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 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

If you have hum

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

The unit does not appear to power on

It may be in Standby mode. Check the rear panel master power switch that it
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 experience a hum through the speakers this can be caused by several
things. The rst 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 preamplier, integrated, receiver or
Amplier o, disconnect the audio cables between it and DirectStream Junior, and
see if the hum goes away when you turn the preamplier, integrated, receiver or
Amplier back on. If it does, it’s most likely a ground loop or buzz from a dimmer.

Troubleshooting xxv

©2016 PS Audio International Inc. All rights reserved.

Troubleshooting

®

Owner’s Reference DirectStream Junior

If this doesn’t solve the problem, reconnect DirectStream Junior and follow these
easy humbusting tips.

Ground loops

The easiest way to gure 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
were working with a receiver or an integrated amplier, you will need to jump to
step 4. If you have a preamp, or processor that is feeding the power amp, your
next step would be to disconnect all inputs to the preamplier or processor. Once
these are disconnected, and the preamp or processor is connected only to the
power amplier, 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.

VCR’s, 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 Wal Mart, Radio
Shack or department store type outlets and is sometimes called a ‘matching
transformer’. If you have problems nding 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

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio International Inc. All rights reserved.

Troubleshooting xxvi

Troubleshooting

®

Owner’s Reference DirectStream Junior

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 9/10th of the work in nding a solution.

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio International Inc. All rights reserved.

Troubleshooting xxvii

Warranty

®

Owner’s Reference DirectStream Junior

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 rst 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

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Warranty 28

Warranty

®

• Alterations or modications to the unit

• Improper or unauthorized repair, including repairs not authorized by PS Audio or a PS Audio authorized repair

center

• Fire, lightning, ood, “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?

Owner’s Reference DirectStream Junior

This warranty is for the benet 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 rst 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 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Warranty 29

Warranty

®

How State Law Applies

This warranty gives you specic 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 specications 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 - [e-mail]
Web - psaudio.com

Owner’s Reference DirectStream Junior

4826 Sterling Drive, Boulder, CO 80301

PH: 720.406.8946 [e-mail] www.psaudio.com

©2016 PS Audio Inc. All rights reserved.

Warranty 30