Audio Research REFERENCE PHONO 10 User manual

User Guide
H I G H D E F I N I T I O N ®
REFERENCE 10
Stereo Preamplifier
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2Contents
Preface 3
Illustrations
Audio Chassis 4
Power Supply Chassis 5
Warnings 6
Installation
Installation of Vacuum Tubes 7
In Your System 8
Connections 9
Operation
Power-Up Procedure 10
Front Panel Controls 11
Remote Control Only Controls 12
Interactive Touch Screen Operation 13 - 16
Troubleshooting 16
Maintenance
Servicing 17
Cleaning 17
Disposal and Recycling Guidelines 17
Limited Warranty 18
Specications 19
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3
Thank you for selecting the Reference 10 as part of your
music listening system. The engineers and designers at
Audio Research have spent countless hours of listening
and testing to create a preamplier of the highest caliber
for music reproduction. The Reference 10 has been
designed to provide you many years of playback.
Please take a few minutes to read through this guide
to help you better understand and optimize your new
preamplier. If you have any questions regarding the
operational functions, contact your dealer or distributor
for assistance.
Sit back and enjoy your new preamplier and the
enhancements it will bring to your system. The
Reference 10 will bring new life to your entire music
collection.
Happy listening!
Preface
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4
Audio Chassis
RIGHT INPUTS
LEFT INPUTS
1
1
2
2
3
3
4
4
5
5
6
6
PROC
PROC
RECORD OUT
RECORD OUT
MAIN OUTPUTS
MAIN OUTPUTS
FROM POWER SUPPLY
CABLE "A"
FROM POWER SUPPLY
CABLE "B"
PLYMOUTH, MINNESOTA
MADE IN U.S.A.
REFERENCE 10
STEREO PREAMPLIFIER
RIGHT OUTPUTS
LEFT OUTPUTS
SERIAL
RISK OF ELECTRIC SHOCK
DO NOT OPEN
CAUTION
!
RS232
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
Illustrations
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5
PLYMOUTH, MINNESOTA
MADE IN U.S.A.
REFERENCE 10
STEREO PREAMPLIFIER
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.
RISK OF ELECTRIC SHOCK
DO NOT OPEN
CAUTION
!
VOLTS
SERIAL
TO AUDIO CHASSIS
CABLE "A"
TO AUDIO CHASSIS
CABLE "B"
235W MAX 50/60 HZ
~
REMOTE TRIGGER
+12V
6A FUSE
SLO-BLO
T4A (230V)
CAUTION
FOR CONTINUED PROTECTION AGAINST
FIRE HAZARD REPLACE FUSE ONLY
WITH SAME TYPE AND RATING
Power Supply Chassis
Illustrations
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6Warnings
To prevent re, or shock hazard, do not expose your Reference 10 to rain
or moisture.
This unit contains voltages which can cause serious injury or death. Do
not operate with cover removed. Refer servicing to your authorized Audio
Research dealer or other qualied personnel.
The detachable power cord on your Reference 10 is equipped with a heavy
gauge, 3-conductor cable and a standard three-prong grounding plug. For
absolute protection, do not defeat the ground power plug. This provides
power line grounding of the Reference 10 chassis to provide absolute
protection from electrical shock.
For continued protection against re hazard, replace the fuse only with the
same type and rating as specied at the fuse holder.
The appliance coupler at the rear of this unit must be accessible for
emergency power disconnect.
A note about packaging...
Save all packaging in a dry place away from re hazard. Your Reference
10 preamplier is a precision electronic instrument and should be properly
cartoned any time shipment is made. You may not have occasion to return
your unit to the factory for service, but if that should prove necessary, or
other occasion requiring shipment occurs, the original packaging will protect
your Reference 10 from unnecessary damage or delay.
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7
Installation
Installation of Vacuum Tubes
Before operating the Reference 10...
This unit has been shipped with the vacuum tubes installed in protective
foam in a separate box packed inside the shipping carton. Remove the
tubes carefully from the protective foam. Using a phillips-head screwdriver
to loosen the fastening screws, remove the top cover and set aside.
After removing the top cover and the vacuum tubes packed in protective
foam, see the accompanying illustrated sheet (g. 1 + 2) for instructions
on installing the tubes for your Reference 10 in their proper locations in the
power supply and audio chassis. Note that the numbers written on each
tube correspond to a ‘V’ number printed on the circuit board next to each
tube socket. Insert each tube rmly, carefully aligning the tube pins with the
corresponding socket holes.
V1V5
V7 V3
V2V6
V8 V4
TOP VIEW
AUDIO UNIT
g. 1
V9
TOP VIEW
POWER SUPPLY
UNIT V10
V11
V12
g. 2
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8Installation
In your System
While the Reference 10 does not dissipate an unusual amount of heat,
it is important that it be provided with reasonable airow to assure long,
trouble-free operation. In addition, the following installation guidelines will
help insure maximum sonic performance as well as reliable service:
Operate unit in upright and horizontal position, prefer-ably on solid, non-
metal shelving.
Do not stack the preamp on top of a power amplier: not only could this
cause overheating, but hum may be introduced into the preamp from the
proximity of the amplier’s power transformer.
Do not stack components or other objects directly on top of the Reference
10.
Do not place or operate your preamp on a soft or irregular surface such as
a rug. This will prevent proper ventilation.
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 qualied personnel).
Ensure a minimum of 8-10” clearance above the unit when placed on
shelving.
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9
Connections
Analog Connections
Input Connectors: The Reference 10 provides seven pairs of BAL/SE
input connectors: 1, 2, 3, 4, 5, 6, and Processor. The BALANCED/SINGLE
ENDED selector (touch screen) or BAL/SE (remote) should be selected to
match the type of connection used (BAL or SE) on each input.
Connect either the BAL or SE connectors for each input. Never connect
the BAL and SE connectors simultaneously for each input.
Output Connectors: Two pairs of BAL/SE main outputs are provided.
Record Output: The BAL/SE tape outputs should be connected to your
recorder’s ‘Record’ or ‘Line’ inputs. These outputs provide a xed-level
two-channel signal (L, R) 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 (e.g. 5 or
6). The signal will then be routed to the Record Out connectors when that
input source is selected.
RS-232 Connection: The RS-232 connection allows for remote control via
systems such as Creston or other automation systems.
12V In/Out Start Jacks: The +12V DC input/output jacks provide the
ability to remotely turn on and off other linked components such as power
ampliers having similar capabilities.
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10 Operation
Power-Up Procedure
Secure all rear-panel connections between Reference 10, power amplier(s)
and input sources.
Plug three-prong power cord from rear of chassis into grounded A.C. wall
outlet. The Power switch defaults to ’off’ when the unit is plugged into a
power receptacle.
Press power switch (either remote or front panel). The screen will initially
display ‘Now Loading’ for a few seconds, after which it will display the Audio
Research logo followed by ‘Reference 10’ (g. 3 + 4). The main display
screen will then appear on the screen, and ‘MUTE’ will be ashing. Once
‘MUTE’ becomes solid, depress the front panel MUTE button (right button)
or touch the word ‘MUTE’ on the screen to initiate normal operation.
Select input source, then BAL or SE as necessary.
Shut-Down
Activate ‘Mute’ function.
Set Volume level to 0.
Turn off power amplier(s).
Press Power switch to ‘off’.
Turn off input sources.
g. 3 g. 4
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11
Operation
Front Panel Controls
The Reference 10 has one microprocessor-driven rotary control and two
buttons (Power and Mute).
Rotary control: Adjusts Volume (output level) up or down for both L and R
channels, and adjusts the balance when the balance function is selected
on the main screen. Volume control is also selectable via Vol UP and Vol
DN 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.
Power On/Off: (left button beneath rotary control) Supplies power from
A.C. wall outlet to preamp; indicated by active display window.
The Reference 10 requires approximately 40 seconds to warm up; this time
is required to stabilize the power supply. See ‘Power-Up Procedure’ on
the adjacent page for details. The same cycle also occurs in the event of a
power interruption.
Mute: (right button beneath rotary control) When activated, electrically
mutes all output of the preamplier; 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
amplier and speakers from unexpected signal pulses. When deactivated,
‘Mute’ disappears from the display window allowing normal operation.
The Reference 10 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 40-second warm-up timer will restart and ‘Mute’
will ash 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, amplier failure or speaker
malfunction.
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12
Remote Control only Functions
Input 1-6: Allows direct selection of each of the 6 inputs of the Reference
10.
Processor (PassThru): Selects external A-V (home theater) processor as
input source and controller of volume level for R and L channels. Reference
10 provides Unity Gain when this input is selected.
When engaged, ‘Pass Thru’ will appear in the display, and the gain is xed
and not adjustable. The preamp will also mute the input after ‘Pass Thru’
is engaged.
Before unmuting the ‘Pass Thru’ input, be sure to turn the volume down on
the home theater processor. Never connect a source with a xed level output
(DVD player, tuner, CD, etc.) to the ‘Pass Thru’ input or the amplier(s) and
speaker system could be damaged when the Reference 10 is unmuted.
BAL/SE: Select as appropriate for each input. For source components
having balanced (XLR) connections to the Reference 10, select BAL. For
single-ended (RCA) sources, select SE. Once selected for an input source,
the setting is memorized.
Invert: Inverts absolute phase of the output signal.
Mono: Sums L and R input for mono output from any source selected.
Display Down/Display Up (DSP DN/DSP UP): Decreases/increases
display intensity, offering 6 levels of brightness and display ‘off’. In display
‘off’ mode the display will illuminate for 10 seconds when any button (except
Power on/off) is selected, allowing for control function navigation.
Balance (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.
Hours: When pressed, displays number of operating hours vacuum tubes
have been in service. NOTE: After replacing tubes, this function should
be reset to ‘0’. See further instructions under ‘Hours Meter’ in the section
‘Interactive Touch Screen Operation’ for details.
Operation
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13
Interactive Touch Screen Operation
The Reference 10 has been designed with a 7” interactive touch screen for
reliable and easy usage. The interface is programmed so that the desired
item for change simply needs to be touched to either toggle between
functions, or bring up a secondary menu for function selection.
Input Selection: To change inputs, touch the currently displayed input
name on the screen. The input bar will appear, listing all seven input options.
Touch the desired input to change (g. 5).
Balanced/SE, Stereo/Mono, Phase 0/180: To change any of these
functions, touch the word you wish to affect and it will toggle between the
two different options for each category (g. 6).
Mute/Operate: Toggle mute on and off by touching the screen where
‘MUTE’ or ‘OPERATE’ is displayed. You may also use the right button
beneath the rotary control to toggle between mute and operate.
g. 5
g. 6
Operation
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14 Operation
Balance: Touch the balance icon located in the top right position of the
screen (it appears as a double ramp). The balance slider will appear beneath
the input name. Using the rotary control, adjust the balance as needed
to right or left channels. When the balance is not at center, a ‘+’ sign
will appear to the right or left side of the balance icon indicating to which
channel the balance is offset. To re-center balance, either use the rotary
control to bring the balance back to center or touch the inverted triangle
above the balance slider (g. 7).
SETTINGS MENU
Touching the settings icon located in the bottom right of the screen (it
appears as a gear) brings you to a submenu with different options related
to the setup and functionality of the Reference 10 (g. 8).
Input Names: Selecting Input Names will allow you to customize the
names of each input on the Reference 10. Once selected, the input bar will
appear at the top of the screen with an alphanumeric keyboard below it. To
change the name of any input, simply touch the input until it is highlighted
and type in the new name. When input naming is complete, select ‘DONE’
to go back to the settings menu.
g. 7
g. 8
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15
Operation
Input Gain Offset: You may experience some devices playing consistently
louder than others (for example, a CD player may always play louder than a
turntable). In this event, the Input Gain Offset can be engaged to balance
the overall volume between the differing inputs, alleviating the need to adjust
the master volume when changing between inputs. The Input Gain Offset
screen is designed so you can make adjustments easily to each input in real
time. For best results, play all devices connected to the Reference 10
simultaneously, and from the Input Gain Offset page, change inputs by
touching the input bar. If an input is louder or softer than another, use the
up and down arrows to adjust accordingly (g 9).
Hours Meter: The Hours Meter displays the total number of hours the
Reference 10 has been running. This is useful to gauge tube life and prepare
for eventual replacement. The hours meter may be reset after the tubes
have been changed by touching the ‘Reset’ button located in the bottom
right of the screen.
Foreground/Background Color: The Reference 10 has ten color options
for both screen background and text. Selecting either one of these options
from the settings menu will allow you choose a new color to customize the
display on your Reference 10. Please note that the currently selected color
is not displayed in the choices shown, nor do you have the option to choose
the same color for both the background and foreground (g. 10).
g. 9
g. 10
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16 Operation
Display Intensity: Display Intensity adjusts the backlight for the screen
and its overall brightness. There are six levels plus ‘off’, with ‘6’ being the
brightest. When ‘off’ is selected, the display will remain on for 8 seconds
and then shut off. To return illumination to the screen, simply touch it or
press a button on the remote. When adjusting the brightness, the words
‘Display Intensity’ will reect the overall setting seleted. The display intensity
can also be adjusted from the remote using the ‘DSP UP’ and ‘DSP DN’
buttons.
About: Touching the ‘About’ button displays a screen with the current
software version of the Reference 10. This information can be useful in
the event the Reference 10 needs troubleshooting. In the bottom right of
the About screen is a ‘Defaults’ button. Selecting the defaults button will
return all settings in the Reference 10 as they were shipped from the factory.
Please note that resetting the Reference 10 back to factory settings does
NOT reset the hours meter.
Troubleshooting
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.
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17
Maintenance
Servicing
CAUTION: Your Reference 10 contains sufcient 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 qualied technician.
The vacuum tubes inside your Reference 10 are quality tubes and with
normal use should not need to be changed for approximately 4,000 hours
of use. Replacement tubes should be of equivalent quality and are available
from Audio Research. Note that tube numbers (V1, V2 etc.) match printed
numbers next to tube sockets on circuit board.
Should service be necessary, please contact your Audio Research dealer,
or Audio Research Customer Service at 763-577-9700.
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 ngerprints or
similar smudges. Cleaners containing abrasives should not be used as they
will damage the anodized nish 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 landll. 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.
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18 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 specic terms, conditions and remedies for fulllment
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 specic terms and remedies for fulllment 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 fulll 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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19
Specications
Frequency Response: +0 -3dB 0.1Hz to 200kHz at rated output. (BALANCED, 200k ohms load.)
Distortion: Less than .006% at 2V RMS Balanced output.
Gain: Main output (SE or BAL input): 12dB Balanced output, 6dB Single Ended output. Tape output: 0dB. (Pro-
cessor input: 0dB Balanced)
Input Impedance: 120K ohms Balanced, 60K ohms SE, Inputs (7): 1, 2, 3, 4, 5, 6, PROCESSOR. (XLR and RCA
connectors).
Output Impedance: 600 ohms Balanced, 300 ohms SE main (2), 20K ohms minimum load and 2000pF maximum
capacitance. Outputs (3): 2 main, 1 tape (XLR and RCA connectors).
Output Polarity: Non inverting.
Maximum Input: 20V RMS maximum Balanced, (10V RMS SE).
Rated Outputs: 2V RMS (1V RMS SE) into 200K ohm balanced load (maximum balanced output capability is 30V
RMS at less than 0.5% THD at 1kHz).
Crosstalk: -80dB or better at 1kHz.
Controls: Volume (104 steps). Push Buttons: Power, Mute, Interactive Touch Screen. Rear RS-232 control and
IR input.
Power Supplies: Electronically regulated low and high voltage supplies. Automatic 40 sec. warm-up/brown-out
mute. Line regulation better than .01%.
Noise: 1.7uV RMS residual IHF weighted balanced equivalent input noise with volume at 1 (109dB below 2V RMS
output.)
Tube Complement: (8)-6H30P dual triodes, plus (2 each) 6550C and 6H30P in power supply.
Power Requirements: 100-135VAC 60Hz (200-270VAC 50/60Hz) 220 watts. Standby: 2.2 watts.
Dimensions: Width 19” (48 cm)
Height 7” (17.8 cm) (standard rack panel)
Depth 15.5” (39.4 cm)
Handles extend 1.5” (3.8 cm) forward of the front panels.
Weight: Audio Chassis: 23.6 lbs. (10.7 kg) Net; 33.3 lbs. (15.1 kg) Shipping.
Power Supply Chassis: 37.65 lbs. (17.07 kg) Net; 47.35 lbs. (21.48 kg) Shipping.
This unit is RoHS compliant
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Specications subject to change without notice.
©2013 Audio Research Corporation.
H I G H D E F I N I T I O N ®
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