Audio Research DSPre User manual

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Owner’s Manual
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DSPre
Stereo Preamplifier DAC

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Contents
Model DSPre Stereo Amplifier
Illustrations 4
Remote functions 5
Preface 6
Warnings 6
Packaging 6
Description of Controls 6 – 7
Programming Input Names 7
Connections 7 – 8
Installation Instructions 8
Operating Procedure 8
Tape Recording Procedure 8
Software Installation 9 – 13
Troubleshooting Guide 14
FCC and Safety Warnings 14
Servicing 14
Cleaning 15
Disposal and Recycling Guidelines 15
Limited Warranty 15
Specifications 16

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CAUTION
FOR CONTINUED PROTECTION AGAINST
FIRE HAZARD REPLACE FUSE ONLY
WITH SAME TYPE AND RATING WARNING
TO PREVENT FIRE AND SHOCK HAZARD, DO NOT
EXPOSE THIS DEVICE TO RAIN OR MOISTURE.
UNIT MUST BE OPERATED IN A HORIZONTAL POSITION.
-DO NOT OPERATE WITH COVERS REMOVED-
UNIT CONTAINS VOLTAGES WHICH MAY BE HAZARDOUS.
1A FUSE
SLO-BLO
T1.0A (230V)
+12V REMOTE
TRIGGER
STEREO DAC PREAMPLIFIER
~
RISK OF ELECTRIC SHOCK
DO NOT OPEN
CAUTION !
PLYMOUTH, MINNESOTA
MADE IN U.S.A.
MODEL DSPre
VOLTS
SERIAL
RS-232 IR
INPUT
USB2.0HS RCA BNC AES/EBU TOSLINK
BAL1 BAL2 SE1 SE2 SE3
PROC
REC BAL SE
BAL1 BAL2 SE1 SE2 SE3
PROC
REC BAL SE
20W MAX
50/60HZ
DIGITAL INPUTS
OUTPUTS
RIGHT ANALOG INPUTS
OUTPUTS
LEFT ANALOG INPUTS
INPUT
VOLUME
POWER SAMPLE MENU ENTER MONO INVERT MUTE
STEREO DAC PREAMPLIFIER DSPre HIGH DEFINITION
D E F I N I T I O N S E R I E S
®

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Note: All DSPre functions are available on the DSPre
hand held remote controller. All functions are
indicated in the display window as they are selected.
See ‘Description of Controls’ in this manual for more
information.
DISPLAY
BAL L BAL R
INVERT
MONO
POWER
VOL DN VOL UP
MENU
DSPre
ENTER
BAL1 BAL2 SE1
SE2 SE3 AES
BNC RCA USB
PAUS E
PLAY
SAMPLE
TOS
MUTE
PROC FILTER

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Preface
Please take time to carefully read and understand
the following instructions before you install or
attempt to operate your Audio Research DSPre
preamplifier.
Becoming familiar with the product and its correct
operating procedures will help assure you of
maximum musical enjoyment and reliable
operation. The effort you invest now will be well
rewarded in the years ahead.
Warnings
1.To prevent fire or shock hazard, do not expose this
product to rain or moisture.
2.This unit operates on voltages which can cause
serious injury or death. Do not operate with covers
removed. Any necessary servicing should be
carried out by your authorized Audio Research
dealer or other qualified electronics technician.
3.The power cord supplied with this unit is safety
tested and is equipped with a proper grounding
plug. If used normally, it will provide a safe earth
ground connection of the chassis. Defeat of the
grounding plug or use of a power cord without a
grounding plug, or any unauthorized modification
of the active circuitry or controls of this unit,
automatically voids warranty coverage, and
could cause injury or death.
4.For safe operation and protection against fire
hazard, replace fuses only with those of the same
type and rating as those supplied with this unit.
Packaging
Save all packaging accompanying this product.
You have purchased a precision electronic
instrument, and it should be properly cartoned any
time shipment becomes necessary. It is very
possible that this unit could be damaged during
shipment if repackaged in cartoning other than
that designed for it. The original packaging
materials help protect your investment from
unnecessary damage, delay and added expense
whenever shipment of this unit is required.
Description of Controls
Front Panel Rotary Controls
The DSPre has two microprocessor-driven rotary
controls.
The rotary control on the left adjusts Volume (output
level) up or down for both R and L channels.
Volume control is also selectable via Vol DN and
Vol UP buttons on the remote control. Volume
adjustment is indicated in the display window by
numeric digits on 0–103 scale.
Do not turn volume up beyond normal listening
levels when “mute” is engaged to avoid
unexpected or possibly damaging sound levels.
Reduce volume level whenever changing input
sources, even when muted.
The rotary control on the right selects any of five
analog inputs sources (BAL1, BAL2, SE1, SE2 and SE3)
and five digital input sources (USB 2.0HS, RCA, BNC,
AES/EBU and Toslink). Each of these sources may
also be selected via direct access buttons on the
remote control. The selected source is indicated in
the display window.
Front Panel and DSPre Remote Control Buttons
Power On/Off: Supplies power from A.C. wall outlet
to preamp; indicated by active display window.
Function also on remote control.
For approximately 90 seconds after start up, ‘Mute’
appears in the display window and flashes until the
automatic muting cycle is completed. This also
occurs in the event of power interruption. Upon
completing the cycle, “Mute” will cease flashing.
The preamp will remain muted until normal
operation is selected by pressing the “Mute”
button.
Mute: When activated, electrically mutes all output
of the preamplifier; indicated by “Mute” in display
window. This control should be activated before
switching inputs, changing connections or shutting
down your audio system to help protect your
amplifier and speakers from unexpected signal
pulses. When deactivated, “Mute” disappears from
the display window allowing normal operation.
Function also on remote control.
The DSPre also has automatic muting to help
protect system components during A.C. power
interruptions or low line voltage. When sensing these
conditions, the preamp automatically goes into
‘Mute’ and disables all outputs. The 90-second
warm-up timer will restart and ‘Mute’ will flash in the
display window when normal power conditions
have been restored.
Note that automatic muting is only designed to
protect against power line interruptions or severe
voltage drop. It will not mute in the event of
subsonic transmissions from a faulty input source,
amplifier failure or speaker malfunction.
Mono: Sums L and R input for mono output from
any source selected. Remembers setting for each
input.
Sample: Selects the sample rate for a digital input.
Invert: Inverts absolute phase of the output signal.
Menu: Enters the DSPre into Input Name program
mode.
Enter: Used in conjunction with the Menu button
and Input Name program mode.
DSPre Remote Only
Volume Up/Down: Increases/decreases overall
volume level of both channels equally for

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whichever input has been selected. Caution: do
not turn up volume beyond normal listening levels
when “Mute” is engaged to avoid unexpected or
possibly damaging sound levels. It is a good idea to
reduce volume whenever changing program
sources, even when muted. Function available on
remote control buttons and front panel rotary
control on left.
Processor (PROC): May be selected by button on
front panel or on remote control. Selects external A-
V (home theater) processor as input source and
controller of volume level for R and L channels
when processor is connected through the
SE3/PROC input only.DSPre provides Unity Gain
when this input is selected.
When engaged, ‘PROC’ and ‘UNITY GAIN’ will
appear in the display, and the volume control is not
adjustable because gain is fixed. The preamp will
also mute the input after ‘PROC’ is engaged. To
disengage processor unity gain operation, press the
SE3 button on the remote. The SE3 input returns to
normal volume control operation and is muted at
zero volume level.
Warning
Before unmuting the ‘PROC’ input, be
sure to turn the volume down on the
home theater processor. Never
connect a source with a fixed level output (DVD
player, tuner, CD, etc.) to the PROC input or the
amplifier(s) and speaker system could be damaged
when the DSPre is unmuted.
Display: Selects one of seven display illumination
levels, including off. When off, the display can be
reactivated for 10 seconds at a low level by
pressing any button (except Power) on remote or
control on front panel.
Bal L/Bal R: Adjusts balance left or right. Adjustment
appears in display window as movable marker on
bar graph. Useful for compensating for uneven
speaker placement or imbalanced output from a
phono cartridge.
Filter: Choose between sharp and soft digital roll-off
filters for the S/PDIF inputs only.
Navigation Pad: The up/down/left right arrow
buttons allow navigation of the setup menu for the
DSPre. The remote control also features USB
interface controls. When the DSPre is connected to
a USB source component (Apple or PC, for
example) which is configured with appropriate
software or programs (iTunes®, Windows Media
Player, etc.) the remote control should be able to
control the USB source component to PLAY/PAUSE,
TRACK ADVANCE and TRACK BACK.
Because of the wide variety of operating systems
and software programs, Audio Research cannot
guarantee that the USB interface will control your
particular USB source product.
Programming Input Names
1.Push the MENU button once to enter input
naming function.
2.Press the button on the remote which
corresponds to the input to be named; or from
the front panel, use the input select knob to select
the input you want to name.
3.Use the volume arrows on the remote or the
volume control on the front panel to scroll
through the name options.
4.Push the ENTER button to select one of the name
options for that input.
5.Use the input select knob or remote control to
select another DSPre input to be named.
6.If you wish to create your own name, scroll to A-Z
and 0-9 and use the up-down arrows on the
remote to choose each letter/number in the
name. The naming option automatically
advances to the next letter/number until you
press enter twice to end the selection for that
name (six characters max).
7.Repeat steps 3-6 until you have completed
selecting input names.
8.Press MENU again to end the input naming
option.
Connections
Input Connectors: The DSPre provides five L/R sets
of analog input connectors: BAL1, BAL2, SE1, SE2,
and SE3/PROC, and five sets of digital input source
connectors: USB 2.0HS, RCA, BNC, AES/EBU and
Toslink.
Output Connectors: One pair of balanced and one
pair of single ended main outputs are provided.
REC Output: The BAL/SE REC outputs should be
connected to your recorder's “Record” or “Line”
inputs. These outputs provide a fixed-level two
channel signal (R, L) to your recorder from
whichever input is selected. The non-variable
output level will be the same as the output of the
selected source.
It is possible to dub or copy from one recorder to
another by connecting the output of the source
recorder to an unused set of stereo inputs (BAL1,
BAL2, etc.). The signal will then be routed to the
Record Out connectors when that input source is
selected.
12V In/Out Remote Power Jacks: The +12V DC
input/output jacks provide the ability to remotely
turn on and off other linked components such as
power amplifiers having similar capabilities.
RS-232 Connection: The RS-232 connection allows
for control via systems such as Creston or other
automation systems.

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IR Input: The IR input allows a wired IR connection
to the DSPre. This connection will defeat the front
panel IR receiver.
Installation Instructions
While the DSPre does not dissipate an unusual
amount of heat, it is important that it be provided
with reasonable airflow to assure long, trouble-free
operation. In addition, the following installation
guidelines will help insure maximum sonic
performance as well as reliable service:
1.Operate unit in upright and horizontal position,
preferably on solid, non-metal shelving.
2.Do not stack the preamp on top of a power
amplifier: not only could this cause overheating,
but hum may be introduced into the preamp
from the proximity of the amplifier's power
transformer. Do not stack components or other
objects directly on top of the DSPre.
3.Do not place or operate your preamp on a soft or
irregular surface such as a rug. This will prevent
proper ventilation.
4.Do not operate your preamp without the top and
bottom covers installed. These are required both
for safety as well as shielding from interference
(except in service operations by qualified
personnel).
For instructions pertaining to the installation of the
DSPre software for USB operation, please refer to
page 10.
Operating Procedure
Start Up
1.Secure all rear-panel connections between
DSPre, power amplifier(s) and input sources.
2.Plug three-prong power cord from rear of chassis
into grounded AC wall outlet. The Power switch
defaults to ‘off’ when the unit is plugged into a
power receptacle.
3.Press power switch (either remote or front panel).
‘Mute’ will will flash in the display window for
approximately 90 seconds, then cease flashing
and remain in the display. Press ‘Mute’ to initiate
operation.
4.Select input source.
Shut Down
1.Activate ‘Mute’ function.
2.Set Volume level to ‘0’.
3.Turn off power amplifier(s).
4.Press Power switch to ‘off ‘.
5.Turn off input sources.
Tape Recording Procedure
When using the DSPre as a control center for
recording, the program source to be recorded must
be connected to one of the five analog inputs
controlled by the Input selector switch or to the
Processor input. This routes the selected program to
the Record output.
Note: If the Processor input is activated by
selecting the ‘Processor’ switch position, all other
inputs will be deactivated. When recording from
the Processor input to the Record out of the DSPre,
the level of the recording will be dependent on the
level setting of the processor.
If you own a three-head tape deck, and wish to
monitor the actual tape while making a recording
(for a true ‘A-B’ comparison of signals before and
after recording), connect the tape deck output to
the Monitor input.
It is also possible to dub from one tape deck to
another. Simply connect the output from one tape
deck to an unused set of inputs controlled by the
Input selector (BAL1, BAL2, SE1, etc.) on the DSPre.
This signal will then be routed to the second tape
deck through the REC output when the appropriate
input is selected on the Input selector.

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WINDOWS PC SOFTWARE INSTALLATION
INSTRUCTIONS:
Installation of the DSPre HD Audio Device drivers is
only necessary if you intend to use the USB 2.0 HS
input on your DSPRE. Software installation is not
necessary if you only intend to use the S/PDIF or
AES/EBU inputs.
Place the installation disk you received with your
DSPre into your computer and double click the
SETUP icon. The disk should auto load and start the
install function; follow the on screen prompts as you
install the DSPre HD Audio device drivers.
Press NEXT when the WELCOME window appears.
When asked to accept or decline the License
Agreement; check the ACCEPT box and press NEXT.
The installer will automatically place the HD Audio
Device Drivers in your Program files. Press the
INSTALL button to continue.
In several spots the computer may prompt you to
“Install, Continue or Don’t Install” the HD Audio
Drivers. Select “allow, continue or Install this driver
software anyway” each time you are prompted.
You will be informed when the installation has
completed successfully; press NEXT to continue.

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At the end of the installation the install program will
ask you to disconnect and reconnect your DSPre to
the computer via the USB port and turn it on. On
Vista and Windows 7, Windows will detect the new
DSPre hardware and load on the new drivers
automatically; on XP, Windows will pop-up with a
NEW HARDWARE FOUND panel; follow the Windows
prompt instructions and your new DSPre HD audio
device drivers will install. The install prompts will
occur twice before the install is complete. Now you
can press FINISH and the installation will be
complete. Normally restarting your PC at this point
is not required but If you do not see the “DSPre OUT
1/2" listed in the SOUND panel after installation you
should do a restart of your PC; see page 14 for
details.
The DAC8 USB drivers are used in the
DSPre. All of the software during the
installation process will be labeled
DAC8.
MAC SOFTWARE INSTALLATION INSTRUCTIONS:
Installation of the DSPre HD Audio Device drivers is
only necessary if you intend to use the USB 2.0 HS
input on your DSPre. Software installation is not
necessary if you only intend to use the S/PDIF or
AES/EBU inputs.
Place the installation disk you received with the
DSPRE into your Mac computer and open the install
file on your desk top. Click on the
“AUDIO_RESEARCH_DSPRE.mpkg” icon in the folder.
Follow the on screen prompts as you install the
DAC8 HD Audio device drivers. Press the CONTINUE
button when you see the Welcome panel.
When the installer asks you if you want to do a
Standard install, press the INSTALL button.
At the completion of the install you should see the
INSTALL SUCCEEDED panel. Press the CLOSE button
and the installation will be complete. Restart your

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Mac to complete the installation.
After installation, go to your DOCK and click on the
SYSTEM PERFERENCES and click on SOUND. Make
sure AUDIO RESEARCH CORP DAC8 has been
selected. If not, go into the SOUND panel and click
on the AUDIO RESEARCH CORP DAC8 name and
close out the panel. Remember, to see the DAC8
name in the SOUND panel you must have the DSPre
ON and connected to the USB port. You are now
ready to call up iTunes or any other music
management program and enjoy your NEW DSPre.
SETTING THE SAMPLE RATE ON MAC OS X:
Now go into the FINDER then GO then UTILITIES and
select AUDIO MIDI SETUP. Once in the Audio MIDI
Setup panel click on the PROPERTIES FOR: selection
box and select AUDIO RESEARCH CORP DAC8.
Then do the same for the SYSTEM OUTPUT: and
DEFAULT OUTPUT: selection boxes. Remember, to
see the DSPre name in the Audio MIDI Setup panel
you must have the DSPre ON and connected to the
USB port.
Next go into the AUDIO OUTPUT section of the panel
and select the desired FORMAT (SAMPLE RATE) from
the list; 44100, 48000, 88200, 96000, 176400,
192000.0Hz. Also, 2ch-24bit should be showing in
the window to the right. If you plan to play mostly
44.1 ripped CD’s then select 44.1, 88.2 or 176.4kHz.
This will select the correct Master Oscillator in the
DSPre for CD’s.
USING THE DSPre CONTROL PANEL:
In Windows when you installed the DSPre software
an icon for the DAC8 HD Audio Device control
panel was placed in your computer’s input tray.
Double click the icon and select one of the 6
sample rates listed, 44.1, 48, 88.2, 96, 176.4 or
192kHz; then press Apply and then close the
window by clicking the X in the upper right corner
of the window. The only time you need to go back
to this window is when you want to change the
sample rate mode. Also, as long as the DSPre is
connected to your computer when you turn it on,
the last sample rate you selected will be resent to
the DSPre. Remember, whenever you want to
change the Sample Rate you must exit the music
management program you are using, call up the
DSPre control panel, make the Sample Rate
change, and recall your music management
program and start playing music.
The Mac OS does not allow change of the Sample
Rate by the hardware ASIO driver. With the Mac
the AUDIO MIDI SETUP Utility has control over the
sample rate sent to the DSPre. Remember, the
DSPre defaults to Native mode so it will always lock
on and indicate whatever sample rate is being sent
by the computer. See the Mac installation
instructions for details.

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SETTING THE SAMPLE RATE OR NATIVE MODE IN
WINDOWS:
If your music server or music management software
does not allow you to connect to the DSPre HD
Audio Device drivers directly you can easily tell
Windows Vista or Windows 7 operating systems to
honor Native mode for your music file. While in
Vista or Windows 7 call up the Windows control
panel and select the Sound panel. You should see
the DAC8 Device driver in the list of playback
devices. Select the DAC8 driver and press the SET
DEFAULT button near the bottom of the panel, then
double click the DAC8 picture in the panel and go
to the next figure. If you do not see the DAC8 OUT
1/2 listed in the sound panel after installation, first
make sure your DSPre is connected to your PC via a
high quality USB cable and plugged into an
appropriate AC outlet. If that has been done and
you still do not see the DAC8 listed in the SOUND
panel, you should do a restart of the PC.
Once you have double clicked the DAC8 driver
and pressed the ADVANCED button you will see the
Exclusive Mode properties. If the “Allow application
to take exclusive control of the device” is selected
then the “DAC8 Control Panel” will select the
sample rate.
Otherwise, for NATIVE MODE, “uncheck” the “Allow
application to take exclusive control of this device”,
press APPLY, then close the window. Now whatever
sample rate your music was stored at will be sent to
the DSPre. If this step does not allow your music
management software to take control of the
sample rate being sent to the DSPre you should
simply use the DAC8 control panel to set the DSPre
sample rate to that of the music you are playing.

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SETTING NATIVE MODE IN MAC OS X:
Mac OS X does not allow the music manager, such
as iTunes or SongBird to change the Sample Rate
on a song by song basis. For example, if you set the
sample rate of the DAC8 driver in the AUDIO MIDI
SETUP panel to 176400.0Hz then iTunes will up-
sample a 44.1 CD to 176.4kHz and send it to the
DSPre; the 176.4 LED will be lit. To play a 44.1 CD at
44.1kHz, simply set the sample rate in the Audio MIDI
Setup Utility to 44100.0kHz. See section SETTING THE
SAMPLE RATE ON MAC OS X: for details.
To play your music in bit perfect mode at its native
Sample Rate you will need to purchase and install
software from a third party such as Pure Music®,
Pure Vinyl® or Amarra®. These software packages
provide bit perfect music transfer to the DSPre and
allow the native sample rate to be sent to the DSPre
on a song by song basis.
GETTING THE MOST OUT OF YOUR DSPRE:
The DSPre has many new features that can be
enhanced when used with some of the top MUSIC
MANAGEMENT software packages and computer
to S/PDIF conversion hardware. Please take a
moment to read through this section and see if
you’re getting the most out of your DSPre setup.
S/PDIF, USB 2.0 HS and MUSIC MANAGEMENT:
The DSPRE was designed to provide your high-end
audio system with bit perfect 24 bit audio at sample
rates not possible from a CD or SACD player. Red
Book CD’s are recorded at 16 bits, 44.1kHz sample
rates; your DSPRE is capable of playing back digital
music recorded at 24bits and sample rates up to
192kHz. With your DSPre you can:
Take the S/PDIF output from your current CD or DVD
player and enjoy the sonic benefits of the Quad
DAC architecture, low jitter dual master oscillators
and high bandwidth direct coupled differential
amplifiers while playing your favorite CD’s.
It is also possible to take the S/PDIF output from
many of the multiroom home audio systems that
are on the market. AppleTV®, Sonos® and many
others provide wired/wireless multiroom music
management systems that have S/PDIF outputs that
work well with the DSPRE.
If you want to play back S/PDIF music at a higher
resolution and sample rate, you can assemble a HD
music server computer system. Your Audio Dealer
or the HRx web site at
http://www.referencerecordings.com/HRxSETUPS.as
p can give you ideas on how to construct a high
resolution music server that will provide an S/PDIF
signal to the DSPRE.
If you desire to play high resolution music files via
the USB 2.0 HS interface to the DSPre, all you do is
connect your computer to the DSPre via a good
quality high speed USB 2.0 (480Mbps) cable and
install the DSPre HD Audio Device drivers. Once
connected you are ready to sit back and enjoy
your favorite tunes.
A large part of the digital music experience is
managing and organizing your music for fast and
accurate playback through the DSPre to your
audio system. There are several software music
managers available to enhance your music
experience; on PC’s, J Rivers Media Center®,
Mediamonkey® and FooBar® are three that
provide the ability to connect to the DSPre’s HD
Audio Device drivers for bit perfect music playback
in its Native mode. Others such as iTunes®,
SongBird® and Windows Media Player® are
excellent media managers that will play your music
through the “Windows Sound Control” interface. To
assure bit perfect data transfer with these music
managers follow the instructions in the “SETTING THE
SAMPLE RATE OR NATIVE MODE” section. The
resources at http://www.computeraudiophile.com/
and other digital music web sites can help you
select a media manager and provide other
information aimed at enhancing your music
enjoyment.

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Troubleshooting Guide
The USB input is not working?
•Make sure you SELECTED the USB as the input on
the DAC8
•Make sure you installed the DAC8 driver software
from the CD that came with your DAC8 and
make sure the computer recognizes the DAC8 is
connected.
•Make sure you are using a High Speed USB cable,
one rated for 480Mbps.
I don’t see the DAC8 in the SOUND panel on my
Mac or Windows PC computer?
•After you install the DAC8 driver software you
must make sure the DAC8 is connected to the
computer via the USB cable and plugged into an
AC outlet otherwise the computer will not show
the DAC8’s presence in the SOUND panel. In
some cases it helps to RESTART your computer
with the DAC8 still connected; this allows the
computer to finish the installation and place the
DAC8 into the SOUND panel for selection.
The volume is too loud or the audio is distorted using
my Mac computer?
•Check the VOLUME control setting in the AUDIO
MIDI Setup panel. The Volume should be set to
about 0.0dB for both channels. (The Mac
computer allows the customer to increase the
digital volume of the music past 0.0dBm
consequently, the Mac can overdrive the DAC8
and cause distortion. This is not an issue with the
Windows PC where 0.0dBm is the maximum
volume setting.)
The audio intermittently distorts when running with
the USB input?
•Check to make sure you are using your
computers USB 2.0 HS (480Mbps) port. A USB 2.0
FS (12Mbps) port will sometimes work but will
distort. Most PC and Mac computers made after
2008 come stock with USB 2.0 HS ports.
•On your PC go into the Device Manager, then
USB Controller, then USB Root Hub panel and click
on Properties and then Advanced; there it will say
the speed of that USB port.
It is possible for a static discharge to temporarily
disable the microprocessor that allows the controls
to function. If this should occur, depress the ‘Mute’
button, then turn off the preamp and unplug the
preamp from the A.C. receptacle for 60 seconds.
Reconnect the A.C. plug and turn the preamp
back on, along with other components. The
controls should resume normal operation. If the
problem persists, contact your dealer or Audio
Research Customer Service at 763.577.9700.
FCC and Safety Warnings
This equipment has been tested and found to
comply with the limits for a class B digital device,
pursuant to Part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against
harmful interference in a residential installation. This
equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in
accordance with the instructions, may cause
harmful interference to radio communications.
However there is no guarantee that interference will
not occur in a particular installation. If this
equipment does cause harmful interference to
radio or television reception, which can be
determined by turning the equipment off and on,
the user is encouraged to try to correct the
interference by one or more of the following
measures:
Re-orient or relocate the receiving antenna.
Increase the separation between the equipment
and the receiver.
Connect the equipment into an outlet on a circuit
different from that to which the receiver is
connected.
Consult the dealer or an experienced radio/TV
technician for help.
To prevent fire or shock hazard, do not expose this
product to rain or moisture.
Servicing
Because of its careful design and exacting
standards of manufacture, your DSPre should
require no routine maintenance. The remote
control's batteries (AAA) should be replaced once
a year.
Caution
Your DSPre contains sufficient levels of
voltage and current to be lethal. Do
not tamper with a component or part
inside the unit. Refer any needed
service to your authorized Audio Research dealer or
other qualified technician.
Should service be necessary, please contact your
Audio Research dealer, or Audio Research
Customer Service at 763.577.9700.

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Cleaning
To maintain the new appearance of this unit,
occasionally wipe the front panel and top cover
with a soft, damp (not wet) cloth to remove dust. A
mild, non-alkaline soap solution may be used to
remove fingerprints or similar smudges. Cleaners
containing abrasives should not be used as they will
damage the anodized finish of the front panel. A
small, soft paintbrush is effective in removing dust
from bevels, the recessed nameplate and other
features of the front panel.
Disposal and Recycling Guidelines
To dispose of this electronic product, do not place
in landfill. In accordance with the European Union
Waste Electrical and Electronic Equipment (WEEE)
directive effective August 2005, this product may
contain regulated materials which upon disposal
require special reuse and recycling processing.
Please contact your dealer or importing distributor
for instructions on proper disposal of this product in
your country. Or, contact Audio Research
Corporation (763.577.9700) for the name of your
importing distributor and how to contact them.
Packing and shipping materials may be disposed of
in a normal manner.
Limited Warranty
Audio Research Corporation products are covered
by a 3-Year Limited Warranty, or a 90-Day Limited
Warranty (vacuum tubes). This Limited Warranty
initiates from the date of purchase, and is limited to
the original purchaser, or in the case of
demonstration equipment, limited to the balance
of warranty remaining after original shipment to the
retailer or importer.
In the United States, the specific terms, conditions
and remedies for fulfillment of this Limited Warranty
are listed on the warranty card accompanying the
product in its shipping carton, or may be obtained
from the authorized retailer or from the Audio
Research Customer Service Department. Outside
the United States, the authorized importing retailer
or distributor has accepted the responsibility for
warranty of Audio Research products sold by them.
The specific terms and remedies for fulfillment of the
Limited Warranty may vary from country to country.
Warranty service should normally be obtained from
the importing retailer or distributor from whom the
product was purchased.
In the unlikely event that technical service beyond
the ability of the importer is required, Audio
Research will fulfill the terms and conditions of the
Limited Warranty. Such product must be returned at
the purchaser's expense to the Audio Research
factory, along with a photocopy of the dated
purchase receipt for the product, a written
description of the problem(s) encountered, and
any information necessary for return shipment. The
cost of return shipment is the responsibility of the
purchaser.

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Specifications
Frequency Response: +0-3dB, 0.2Hz to 200kHz at rated
output. 0.15dB 20Hz to 20kHz (Balanced, 200k ohms
load)
Distortion: THD+N less than .006% at 2VRMS BAL output.
Signal-to-Noise Ratio: 120dB
Dynamic Range (AES17): 117dB
IMD (SMPTE): .007%
Gain: Max. Analog Gain: 18.1dB Balanced, 12dB SE.
Max. Digital Gain: 30dB Balanced, 24dB SE. (Processor
input: 0dB balanced)
Input Impedance: 120K ohms Balanced, 60K ohms SE.
Inputs: Digital: 75 ohms BNC, RCA, 110 ohms AES/EBU,
OPT 660nm TOSLink fiber 44.1 to 96kHz.
Output Impedance: 500 ohms Balanced, 250 ohms SE
Main (2), 20K ohms minimum load and 2000pF
maximum capacitance. Record 1K ohms to selected
input.
Output Polarity: Non-inverting.
Maximum Input: 24V RMS BAL, 12V RMS SE.
Rated Outputs: 2V RMS 1Hz to 100kHz into 200K ohm
balanced load (maximum balanced output capability
is 15V RMS at less than 0.5% THD at 1kHz).
Digital Sample Rates: 44.1kHz to 192kHz, SPDIF and USB
2.0HS
Master Oscillator: 22.579mHz ±20Hz for 44.1, 88.2 and
176.4kHz. 24.576mHz±20Hz for 48, 96 and 192kHz
sample rates.
Intrinsic Jitter: <10ps
Controls: Rotary volume selector (104 steps) and rotary
input selector.
Push buttons: Power, Mono, Enter, Menu, Sample, Mute,
Invert.
Remote buttons: Display, Power, BAL L, BAL R, Filter,
Pause/Play/Skip forward-backward, Mute, Mono,
Invert, Menu, Enter, Sample, Proc, VOL UP, VOL DN,
Bal1, Bal2, Bal3, SE1, SE2, SE3, AES, BNC, RCA, USB, TOS.
Power Supplies: R-core transformer & 7 low-noise
regulators. Automatic 90 sec. warm-up/brown-out
mute. Line regulation better than .01%
Noise: -96dB (volume at 1)
Crosstalk: -93dB
Power Requirements: 105-130VAC 60Hz (210-260VAC
50/60Hz) 27 watts maximum. Sleep mode 7 watts
maximum.
Dimensions: 19" (48 cm) W x 5.75" (14.6 cm) H (standard
rack panel) x 14" (35.6 cm) D. Handles extend 1.50" (3.8
cm) forward of the front panel.
Weight: 13.2 lbs. (6.0 kg) Net; 19.9 lbs. (9.05 kg)
Shipping.
Specifications subject to change without notice.
©2011 Audio Research Corporation.
3900 Annapolis Lane North
Plymouth, MN 55447
763.577.9700
www.audioresearch.com