JEFF ROWLAND CORUS STEREO PREAMPLIFIER Quick start guide

CORUS STEREO PREAMPLIFIER
Operational Manual
REV05 2010
!
© Jeff Rowland Design Group 2010 All Rights Reserved

IMPORTANT SAFETY INSTRUCTIONS
The preamplifier has been designed to operate at the highest level of efficiency and
performance in any normal operating situation; however, there are a few important use
and care principles that must be kept in mind when operating the preamplifier:
Do not expose the preamplifier to rain, moisture, or excessively damp conditions.
Due to auto-ranging circuitry and dual-stage voltage regulation, the audio
performance will not be affected by any voltage fluctuations within the operating
voltage range. The CORUS PREAMPLIFIER can be operated at any mains voltage
over the range of 85 to 265 VAC without any adjustments necessary.
The CORUS PREAMPLIFIER must not be modified in any way, other than according
to official service bulletins from JRDG (Jeff Rowland Design Group). Otherwise,
the factory warranty will be immediately voided.
Be sure the preamplifier is muted (volume level bracketed) before connecting or
disconnecting any interconnect cables.
When operating the CORUS PREAMPLIFIER, a properly grounded AC receptacle
should be used. A potential shock hazard may result if the supplied 3-wire,
grounded AC cable ground terminal is defeated or lifted or the unit is connected
to a 2-wire ungrounded AC outlet.
The CORUS PREAMPLIFIER is designed to perform optimally with no adjustments
or maintenance for the lifetime of the product. Do not attempt to open the bottom
cover of the preamplifier and refer all service issues to qualified personnel. The
voltages inside the CORUS PREAMPLIFIER can be hazardous.
Because of the energy efficiency of the CORUS PREAMPLIFIER, there is no need to
unplug the unit when not in use; however, the preamplifier can be muted, and/or
display blanked, if desired.
PROTECTIVE SYSTEMS
The CORUS PREAMPLIFIER is equipped with internal fuses for protection against
excessive AC current draw; however, since no protection circuitry or system can
completely protect a product from every electrical hazard, certain precautions should be
observed. In the event of severe voltage hazards such as lightning or when the
preamplifier will not be used for extended periods of time, the preamplifier should be
unplugged from the AC mains to avoid potential damage to the internal circuitry. All other
audio/video system components should also be disconnected from AC mains power as
hazardous voltages can easily travel throughout an interconnected system.
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NOTE FROM JEFF ROWLAND DESIGN GROUP
elcome to the Jeff Rowland Design Group “family” and congratulations on your
purchase of what is unquestionably one of the world’s finest preamplifiers. With
its combination of features such as precision electronic circuitry, exceptional
efficiency, and accurately machined chassis components throughout, your CORUS
PREAMPLIFIER will offer you many years of musically satisfying enjoyment.
Please take a few minutes to read the remainder of this Owner’s Manual before
proceeding with the installation of the preamplifier. A thorough understanding of the
operational features will allow you to gain the maximum performance and ease of use for
which this preamplifier was designed.
Please note that your CORUS PREAMPLIFIER and power supply serial numbers begin with
the letters “PD” and “C” respectively. Please include this number with any
correspondence regarding your CORUS PREAMPLIFIER. It has been my joy to create an
audio component of enduring value that reflects the highest ideals of musical and artistic
expression. It is my hope that these qualities will enrich your experience and pride of
ownership.
If you have any additional questions regarding the installation or operation of the CORUS
PREAMPLIFIER, please contact your authorized Jeff Rowland Design Group dealer or
check the Jeff Rowland Design Group web site at http://jeffrowland.com.
Enjoy the music!
Jeff Rowland
President, Jeff Rowland Design Group
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TABLE OF CONTENTS
.........................................................................................................Special Design Features 5
............................................................................................................Maintenance and Care 8
......................................................................................................Unpacking and Placement 9
..................................................................................................................Initial Inspection 9
...........................................................................................................................Unpacking 9
.................................................................................................Placement and Alignment 10
.............................................................................................................................Front Panel 11
...........................................................................................................Front Panel Display 11
.........................................................................................................Front Panel Controls 13
....................................................................................................................Menu Options 14
..............................................................................................................................Rear Panel 16
.............................................................................................Handheld Remote Transmitter 17
............................................................................................Remote Transmitter Controls 18
...............................................................................................................Internal Switches 18
........................................................................Remote Transmitter Battery Replacement 19
...............................................................................................................General Operations 20
....................................................................................................................Mute Settings 20
..............................................................................................................Channel Balance 20
.......................................................................................Record Select Input Assignment 20
...............................................................................................Adjusting Record Out level 21
...........................................................................................Independent Phase Inversion 21
..........................................................................................................Setting Out 2 Offset 21
...........................................................................................................Setting Input Offset 21
.......................................................................................................Adjusting Out 2 Offset 21
................................................................................................................Factory Restore 21
........................................................................................................................Specifications 22
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SPECIAL DESIGN FEATURES
MACHINED ALUMINUM CHASSIS: Preamplifier circuitry housed inside single ultra-
low resonance, structurally rigid chassis precision-machined from a solid ingot of
aircraft grade 6061-T6 aluminum, completely sealed for trouble-free operation,
yield maximum electrical/EMI/RF isolation.
FUNCTIONAL ISOLATION: Power supply is confined inside external machined
aluminum chassis. Sensitive audio circuits isolated from power supply in main
preamplifier chassis. Left and right channel circuits are further isolated into
individual milled aluminum pockets in a true dual mono design for ultimate RF
and EMI shielding.
FREE OF INTERNAL SIGNAL POLLUTION: Control subsystem taken completely offline
after each command execution to maximize sound purity. All signal switching
relays are “latching” type which only draw current for a few milliseconds during
the switching event then revert to a no current “off” state.
AUTOMATIC WORLDWIDE OPERATIONS: Auto-sensing and auto-ranging SMPS
provides optimum performance at any world-wide mains operating voltage
between 85V and 265V.
CERAMIC CIRCUIT BOARDS: All audio circuits are implemented on military-grade,
multilayer, low dielectric constant, Rogers™ ceramic circuit board substrate for
extremely low energy retention and absorption. Large low impedance ground
planes for extended internal star-grounding. Newly developed ceramic capacitors
replace conventional electrolytic type, resulting in power supply noise decoupling
improvements by an order of magnitude (10X).
SHORTEST SIGNAL PATH: Gain stages, based upon ultra-low noise differential
balanced audio amplifiers, are implemented into the shortest signal path of any
previous Rowland preamplifier. All signal paths are balanced from input to output
for maximum noise rejection.
DUAL-ZONE PREAMPLIFICATION: Separate 2nd gain stage for record outputs offers
same circuitry as the primary signal path with independent volume control.
TRANSFORMER-COUPLED: All inputs and outputs routed through professional
grade Lundahl transformers for maximum common noise rejection, EMI immunity,
and cross-component compatibility. Transformer coupling also ensures invariant
gain for all balanced inputs and outputs. When used with input transformer
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equipped JRDG (Jeff Rowland Design Group) amplifiers a 140dB dynamic range
interface can be achieved. All unbalanced inputs convert to balanced upon
entering the preamp.
FLEXIBLE CONNECTIVITY: 6 inputs (4 XLR balanced, 2 RCA unbalanced); 4 main
outputs (2 XLR balanced, 2 RCA unbalanced); 2 record outputs (1 XLR
balanced, 1 RCA unbalanced); per channel.
INPUT GAIN OFFSETS: Hi resolution independently programmable gain offset on
each main input ranging from -20dB to +20dB in 0.5dB increments.
OUTPUT OFFSET: High-resolution programmable gain offset on MAIN UNBALANCED
OUTPUT 2 (mapped to OUTPUT B on the preamplifier back panel) with 0.5dB
resolution adjustable relative to MAIN OUTPUT 1 (mapped to OUTPUT A on the
preamplifier back panel).
UNITY GAIN INPUTS: Any main input can be configured as unity gain bypass for
compatibility with theater processors.
PHASE INVERSION: Independent signal phase inversion control on left and right
channels for optimum speaker setup and system checks.
CHANNEL BALANCE: Hi resolution (1.0dB) panning of stereophonic image
(channel balance) for a maximum +/-20dB shift.
VFD: Long life 32x320 pixel custom graphic vacuum fluorescent display (VFD)
offers maximum resolution of display data for status indication.
HANDHELD REMOTE TRANSMITTER: Highly ergonomic, custom handheld remote
transmitter milled from aluminum billet supports complete system control and
duplicates front panel operations.
REMOTE SENSOR: Wired remote sensor milled from aluminum billet enables
handheld remote transmitter operation while housing preamplifier in closed
cabinet enclosures.
PRECISION VOLUME ADJUSTMENTS: Dual rate volume control allows precision level
adjustments over nearly a 100 dB range. The volume control incorporates a
permanently noiseless optical encoder that will always maintain its tactile feel,
accuracy, and channel balance at all settings. The volume can be adjusted from
0dB to 99.5dB from the multi-role control knob on the front panel, as well as from
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the multi-function handheld remote transmitter. Rapid turns of the control knob
adjust the volume by 1.5dB increments. Slow turns of the control allow for very
fine adjustments by 0.5dB increments.
QUIET POWER-UP: No turn-on or turn-off transients during intermittent power
interruptions.
CUSTOMIZATION: Inputs can be custom named and set for different gain structures
and automatically stored in internal memory.
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Figure 1: Corus components (cables not shown)

MAINTENANCE AND CARE
All JRDG (Jeff Rowland Design Group) products are designed to provide a lifetime of
enjoyment and listening pleasure.
Chassis is sealed to prevent dust from entering the interior of the chassis and thus
should never need interior cleaning during the lifetime of the product. All internal circuitry
is maintenance-free such that no adjustments of any kind are necessary over the lifetime
of the product. If the preamplifier is ever in need of service, updating, or upgrading, it
should only be returned to an authorized repair facility or technician for servicing.
The front panel of the unit is precision-machined in a unique process that incorporates a
diamond tipped cutting tool. This process was refined over many years to produce an
attractive and unique appearance. Because the surface is not finished in the typical
fashion of most audio and video equipment, there are a few rules that must be kept in
mind when cleaning the equipment.
NOTE: PLEASE ALLOW THE FRONT PANEL, WHICH IS COATED WITH AN AUTOMOTIVE-GRADE
POLYURETHANE FINISH, TO CURE FOR 6 MONTHS BEFORE ATTEMPTING TO CLEAN IT. THIS WILL
PREVENT SMALL SCRATCHES FROM MARRING THE SURFACE BEFORE THE SURFACE COATING
HAS HAD A CHANCE TO HARDEN COMPLETELY.
WARNING: THE FRONT PANEL OF THE UNIT SHOULD NEVER BE CLEANED WITH ANYTHING
OTHER THAN A VERY SOFT COTTON CLOTH AND PLAIN WATER OR FINE OIL-BASED FURNITURE
POLISH. BECAUSE OF THE FINE FINISH OF THE FRONT PANEL, USE OF ANY OTHER CLEANING
AGENT MAY PERMANENTLY SCRATCH THE FINISH.
The top cover, sides and bottom are protected by a durable black anodized finish and
can be cleaned with a soft cotton cloth (such as an optical lens or microfiber cleaning
cloth) dampened with plain water. Water should be applied directly to the cloth and not
the chassis. A very mild plastic or glass cleaner that does not contain ammonia may also
be used. If a mark has been left on the chassis, do not use any type of abrasive or
chemical cleaner to remove the mark.
If you have any questions about the care or cleaning of your CORUS PREAMPLIFIER,
please contact your dealer or the JRDG (Jeff Rowland Design Group) factory before
attempting to clean the chassis. The use of a cleanser or abrasive to clean the chassis
that has not been approved by the factory will almost certainly damage the finish and will
not be covered under warranty.
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UNPACKING AND PLACEMENT
INITIAL INSPECTION
Inspect the shipping container for damage. If any portion of the shipping container,
packing material, preamplifier, or accessories are damaged or missing, notify your dealer
and the shipper (if a claim is to be made) immediately.
NOTE: MANY SHIPPERS REQUIRE NOTIFICATION AND INSPECTION WITHIN 24 HOURS OF
DELIVERY TO DETERMINE THE NATURE OF DAMAGES INCURRED.
Your CORUS PREAMPLIFIER has undergone extensive performance evaluations, listening
tests, quality control inspections, and a minimum 72-hour burn-in period prior to
shipment and should therefore be in perfect operating condition upon delivery. If the
preamplifier does not operate correctly, please notify your dealer immediately.
We strongly suggest that you save all of the packing materials. If the preamplifier is
returned to your dealer or JRDG (Jeff Rowland Design Group), the original packing
materials must be used for shipment to avoid possible damage. Neither JRDG (Jeff
Rowland Design Group) nor the shipper can be held responsible for damages incurred
during transit if the original factory packing is not used. All factory returns require that
JRDG (Jeff Rowland Design Group) issue a Return Authorization (RA) number prior to
shipment.
UNPACKING
Carefully unpack preamplifier chassis and power supply from their original packing box.
Remove all accessory items from the accessory box. Accessories include:
1 Detachable IEC AC Power Cord
2 2-Meter Multi-pin DC Cables
1 Handheld Remote Transmitter Handset
1 Remote Transmitter Sensor
1 2-Meter Remote Transmitter Data Cable
Operational Manual
Warranty Card
IMPORTANT: RETAIN ALL PACKING MATERIALS FOR FUTURE TRANSPORT. SHIPPING PRODUCT IN
INADEQUATE PACKING MATERIALS MAY VIOLATE THE JEFF ROWLAND DESIGN GROUP
MANUFACTURER’S WARRANTY.
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PLACEMENT AND ALIGNMENT
Place the CORUS PREAMPLIFIER on a stable platform, rack, or shelf. The power supply
can be placed up to two meters away from the preamplifier. All audio interconnects can
be inserted into the rear panel at this time. Then each multi-pin DC cable can be inserted
into the DC out receptacles. Partially insert each cable connector shell and rotate until
alignment is achieved. Then firmly push cable shell until it locks in place. A snap will be
felt and heard when the cable is correctly inserted. Repeat the same procedure when
installing the DC cables into the power supply. To remove cables, grasp the outer sliding
sleeve of each cable between your fingers and pull sliding sleeve and cable away from
the chassis connector.
NOTE: DO NOT FORCE CABLE INTO RECEPTACLE UNLESS ALIGNMENT IS ACHIEVED.
After all interconnect and DC cables have been installed into both units, plug in the AC
power cord into the power supply. The other end of the power cord may then be plugged
into any AC mains source from 85 to 265 volts AC. The rocker power switch on the
power supply may be turned on at this time.
NOTE: THE PREAMPLIFIER IS BEST LEFT POWERED ON INDEFINITELY TO ENSURE OPTIMUM
OPERATING CHARACTERISTICS.
WARNING: THE CORUS PREAMPLIFIER MUST BE CONNECTED TO THE POWER SUPPLY VIA THE
DC POWER CABLES BEFORE APPLYING AC POWER TO THE POWER SUPPLY. FAILURE TO
FOLLOW THIS INSTALLATION SEQUENCE MAY RESULT IN DAMAGE TO INTERNAL POWER
SUPPLY COMPONENTS.
10

FRONT PANEL
The front panel of the Corus Preamplifier’s chassis features a vacuum-fluorescent (VFD) display,
10 push-buttons, and a multi-purpose volume/menu control knob.
All controls are precision machined from aluminum billet. Each pushbutton has been designed
with a slightly different length to accommodate the curvature of the faceplate.
FRONT PANEL DISPLAY
Figure 2: Front Panel Display
1. CUSTOM VFD. Long life 32x320 pixel custom graphic vacuum fluorescent display (VFD)
offers maximum resolution of display data for status indication.
2. PHASE INVERSION INDICATOR. The CORUS PREAMPLIFIER’s display features a visible
indicator for the phases of both right and left channels on its lower left corner as follows:
a. L+ +R -- the phase for both channels is Normal (not inverted).
b. L−+R -- left channel inverted.
c. L+ −R -- right channel inverted.
d. L−−R -- both channels inverted.
3. RECORD SELECT INDICATOR. Indicates which input is routed to the RECORD OUTPUT
jacks. If the input is labeled via the MENU function, then the label selected will also be
indicated under the heading. If the input is not labeled, then no indication will be provided. If
inputs 1through 4are selected BAL will be indicated. If inputs 5or 6are selected, UNBAL will
be indicated.
4. RECORD LABEL INDICATOR. Indicates label assigned to input routed to the RECORD
OUTPUT jacks. If no input is selected, then no label will be indicated.
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5. CHANNEL BALANCE/OFFSET INDICATOR. The channel balance indicator is a horizontal
bar graph located to the right of the phase indicator. The cursor changes from a small square
to a diamond shape at the center of the bar graph when the left and right channels have
identical gains, or when no input gain offset has been added to a selected input. Whenever a
channel balance or gain offset is adjusted the cursor will change from a diamond to a square.
Each increment of the cursor is equal to one-half dB of gain offset of each channel, or a one
dB difference between right and left channels.
6. INPUT NUMBER INDICATOR. Indicates which input number is routed to the MAIN
OUTPUT 1/2/B jacks. If inputs 1through 4are selected BAL will be indicated. If inputs 5or 6
are selected, UNBAL will be indicated.
7. INPUT LABEL INDICATOR.If the input is labeled via the MENU function, then the label
selected will be indicated. A complete list of input names is provided in the MENU when the
menu function is selected.
8. VOLUME/MUTE INDICATOR. This display shows the current volume of the selected input
numerically, from 00.0 to 99.5, in 0.5 dB increments. When the preamp is muted the volume
indicator numbers will be surrounded by corner brackets which indicates that the selected
volume will be decreased by 20 dB. The selected volume numbers will also be decreased by
20. When the preamp is fully muted the original volume indicator numbers will be surrounded
by full brackets which indicates that the selected volume will be decreased to zero.
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FRONT PANEL CONTROLS
Figure 3: Front Panel Controls
1. INPUT BUTTONS 1-6. The main input number is selected by pressing the desired
input button.
2. RECORD PUSHBUTTON. Enters the RECORD SELECT mode. The record input number is
selected by pressing the front panel’s RECORD button and then pressing the desired input
button. This can also be done by choosing RECORD SELECT from the MENU. The RECORD
SELECT MODE persists until a main input number is selected.
3. MENU PUSHBUTTON. Enters MENU mode. Also used to select the MENU option and exit
the MENU mode.
4. DISPLAY PUSHBUTTON. Turns display off and mutes the preamplifier. Typically used to
extend the life of the display while maintaining the preamplifier circuitry in a powered status.
5. MUTE PUSHBUTTON. Depressing the MUTE button once will reduce the volume by 20 dB.
Depressing the MUTE button a second time will fully mute the volume. Depressing the MUTE
button a third time will return the volume to the original unmuted condition. Depressing and
holding the MUTE button for approximately 10 seconds forces a hardware reset.
6. VOLUME CONTROL KNOB. Rotation of the volume control knob clockwise will increase the
output level of the CORUS PREAMPLIFIER. Rotation of the knob counter-clockwise will
decrease the output level. The CORUS PREAMPLIFIER features a dual-range volume control
system. Rotating the volume knob slowly will cause the volume to increase or decrease in
small, precise steps. Rotating the knob abruptly will result in large, immediate changes to the
output level.
In MENU mode, rotating the volume knob will scroll through the CORUS PREAMPLIFIER’s
menu and submenus.
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MENU OPTIONS
Several buttons enter and exit the MENU: The front-panel’s MENU button; the handheld
remote transmitter ENTER and EXIT buttons; and the front panel VOLUME knob. From the
display’s main screen, pressing any of the MENU buttons enters the MENU mode. Once in
MENU mode, either the VOLUME knob or the handheld remote transmitter’s Navigation Up
() or Down () buttons scroll through the MENU choices. The menu text scrolls up or
down. After scrolling to the desired menu item, pressing any MENU button again performs
that function and exits the MENU mode.
CANCEL MENU. Pressing any of the MENU buttons will cancel the MENU mode and
return to the display’s main screen.
BALANCE. Adjusts the difference between left and right signal levels in 1.0dB steps.
Adjusting the cursor to the left increases the left channel’s gain in 0.5dB increments,
while decreasing the right channel’s gain in 0.5dB increments, and vice versa. The
adjustment in balance will not affect the overall volume level. Adjusting the balance for
any input will adjust the balance for all inputs. Any balance adjustment will be saved in
the internal memory of the preamplifier even if the power is shut off. Up to a maximum of
+/-20dB offset can be achieved.
STANDBY. Enters STANDBY mode. STANDBY mode must be exited by pressing the front
panel’s Standby button.
RECORD SELECT. Assigns any input selected from the front panel to the record circuitry
and outputs jacks.
PHASE NORMAL. Sets both channels to non-inverting (normal phase). The lower left-
hand corner of the display indicates. (L+ +R)
NOTE: ANY OF THE FOUR PHASE OPTIONS CAN BE SELECTED FROM THE MENU.
HOWEVER, THE PHASE BUTTON ON THE HANDHELD REMOTE TRANSMITTER SIMPLY
TOGGLES BETWEEN PHASE NORMAL AND INVERT BOTH.
INVERT BOTH. Inverts the phase of both channels. (L−−R)
INVERT LEFT. Inverts only the left channel. (L−+R)
INVERT RIGHT. Inverts only the right channel. (L+ −R)
INPUT OFFSET. Adjusts the input gain offset for the most recently selected main input by
up to +/−20dB by turning the VOLUME knob clockwise or counter-clockwise. The balance
bar graph will indicate any degree of adjustment in 0.5dB increments when this mode is
selected. When the cursor is returned to center and resumes its diamond shape no input
offset adjustment has been made.This is feature is particularly useful for sources that
have much higher or much lower output levels than normal. Every individual input offset
adjustments is automatically stored in the preamplifier internal memory until adjusted to a
new value.
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OUT 2 OFFSET. Adjusts the input gain offset of the unbalanced (RCA) OUT 2 output
relative to the balanced (XLR) MAIN OUTPUTS 1and 2by turning the VOLUME knob
clockwise or counter-clockwise.The balance bar graph will indicate any degree of
adjustment in 0.5dB increments when this mode is selected. When the cursor is returned
to center and resumes its diamond shape, no OUT 2 OFFSET adjustment has been made.
Any OUT 2 OFFSET adjustment is automatically stored in the preamplifier internal memory
until adjusted to a new value. Up to a maximum of +/-20dB offset can be achieved.
RECORD OUT LEVEL. Adjusts the level (volume) of the record signal path.
NAME −. . . . . A variety of names for labeling the Main and Record Inputs is provided.
The name chosen is assigned to the last-selected Main or Record Input.
REMOTE DEFAULT. Returns IR receiver frequencies to factory default setting, thereby
matching the handheld remote transmitter transmission frequencies when adjusted to
factory default setting.
REMOTE ALT 1,2, AND 3. Sets IR receiver frequencies to match handheld remote
transmitter transmission frequencies when adjusted to corresponding transmitting
frequencies.
DISPLAY HIGH/MEDIUM/LOW. Adjusts the brightness of the display in three levels.
DISPLAY ON. Cancels DISPLAY OFF 5s/15smodes and returns the display to the
DISPLAY HIGH brightness setting.
DISPLAY OFF 5s. The display remains off during normal operation, and is temporarily
activated for 5 seconds whenever any command is issued through the front panel or the
handheld remote transmitter.
DISPLAY OFF 15s. The display remains off during normal operation, and is temporarily
activated for 15 seconds whenever any command is issued through the front panel or
handheld remote transmitter.
FACTORY DEFAULT. Return all preamplifier settings to factory defaults.
CORUS PREAMPLIFIER FIRMWARE REVISION NUMBER. Indicates current version of
CORUS PREAMPLIFIER operating system software.
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REAR PANEL
Figure 4: Rear Panel
1. DC IN R/L POWER INPUT RECEPTACLES. Two separate DC power cables, one for each
channel, are utilized to connect the power supply to CORUS PREAMPLIFIER.
2. INPUTS. Four (4) pair Balanced (XLR), Two (2) pair Unbalanced (RCA) input jacks for each
channel.
3. MAIN 1/MAIN 2 OUTPUTS. Two (2) pair Balanced (XLR), Two (2) pair Unbalanced (RCA)
jacks for Main A/Main B outputs for each channel. (MAIN 1 and MAIN 2 are mapped to
OUTPUT A and OUTPUT B on the preamplifier back panel)
4. RECORD OUTPUTS. One (1) pair Balanced (XLR), One (1) pair Unbalanced (RCA) jacks for
Record Out.
5. REMOTE SENSOR INPUT CONNECTOR and SERIAL NUMBER. he remote sensor unit
connects to this connector via a 2-meter flexible cable. The wired connection allows full
control of the preamplifier through the infrared handheld remote transmitter. The 2-meter
cable end marked PREAMP END must be connected to the preamplifier rear panel. The
preamplifier chassis serial number begins with the letters “PD”.
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Figure 5: Handheld Remote Transmitter
HANDHELD REMOTE TRANSMITTER
The CORUS PREAMPLIFIER’s infrared handheld remote
transmitter is matched by a remote sensor unit that
connects to the preamplifier via a 2 meter long cable.
The hard wired connection allows the sensor unit to be
placed up to 2 meters away from the preamplifier.
NOTE: AN ACTIVITY LIGHT ON THE HANDHELD REMOTE
TRANSMITTER ILLUMINATES DURING IR TRANSMISSION. A
FAINT ACTIVITY LIGHT IS AN INDICATION THAT THE AA
ALKALINE BATTERIES INSIDE THE HANDHELD REMOTE ARE
DEPLETED, AND NEED TO BE REPLACED.
The handheld remote transmitter features internal
switches for selecting alternate transmission frequency
codes. The switches are accessible by removing the
handheld remote bottom cover. Alternate codes may
be selected to remedy conflicts with other remote
controlled devices. Matching codes must be assigned
to the CORUS PREAMPLIFIER from the MENU.
NOTE: NORMAL CORUS OPERATION UTILIZES THE REMOTE
DEFAULT CODE LOCATED IN THE MENU.
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REMOTE TRANSMITTER CONTROLS
BUTTONS 1 THROUGH 6. Selects the Main Input number. If front panel RECORD
button is pressed, or the RECORD SELECT menu option is selected, the handheld
remote buttons #1 through #6 will select the Record Input Number.
PHASE. Toggles between Phase Normal (L+ +R) and Invert Both (L−−R).
MUTE. The CORUS PREAMPLIFIER’s mute function can be controlled by pressing
the dedicated MUTE button featured on the handheld remote transmitter.
VOLUME +/−.Normally adjusts the Main Input volume. In RECORD OUT LEVEL
mode it adjusts the record volume.
OUT 2 VOL +/−.Adjusts the level of the unbalanced RCA main outputs relative to
the balanced Main Out 1 outputs (XLR/RCA), and Main Output 2 XLR output.
Press ENTER or EXIT to leave this mode.
REC OUT VOLUME +/−.Pressing either button automatically enters the REC OUT
LEVEL menu mode and then adjusts the level of the RECORD outputs (XLR/RCA).
Press ENTER or EXIT to leave this mode.
UP-DOWN ARROWS. /.In MENU mode scrolls the menu text up or down.
LEFT RIGHT ARROWS. /In the BALANCE menu mode - shifts the outputs to
the left or right. In the INPUT OFFSET or OUT 2 OFFSET menu modes - adjusts the
input gain offset up or down.
ENTER. Performs the same function as the front panel’s MENU button.
EXIT. Exits any MENU function.
INTERNAL SWITCHES
Selects the Remote Frequency (custom code) that is transmitted.
All Switches OFF: The Default Remote Code
Switch 1 ON: Remote Code 1.
Switch 2 ON: Remote Code 2.
Switch 3 ON: Remote Code 3.
Switch 4 ON: Enables blinking “finder” LED.
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REMOTE TRANSMITTER BATTERY REPLACEMENT
The CORUS PREAMPLIFIER’s handheld remote transmitter is powered by 2 standard
alkaline double-A (AA) batteries. When the remote transmission range decreases or no
longer operates, the batteries need to be replaced.
Using a standard flat blade screw driver, unfasten the holding screw located in
the bottom end of the transmitter unit.
Remove the spring-loaded cover.
Remove both AA batteries.
Orient the remote transmitter with the keypad facing up, and with the battery
compartment towards you.
Insert a fresh battery into the left barrel with negative pole (flat end) first.
Insert a fresh battery into the right barrel with positive pole (button end) first.
Install the spring-loaded cover.
Gently refasten the holding screw. Do not over-tighten.
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GENERAL OPERATIONS
MUTE SETTINGS
Pressing the MUTE button once on either the control panel or remote transmitter reduces
the main volume by 20dB, and decreases the volume indicator by 20.0 counts. The
display shows the volume indicator surrounded by corner brackets.
Pressing MUTE button a second time mutes the main volume completely. The volume
indicator on the display returns to the normal count, but it is surrounded by full brackets.
Pressing MUTE button a third time returns the CORUS PREAMPLIFIER’s volume to the
original level. Brackets will disappear from the indicator, and the indicator will return to its
original count.
CHANNEL BALANCE
There are two methods to adjust left/right channel balance on the CORUS PREAMPLIFIER:
From the Preamplifier Control Chassis
Enter MENU. Scroll to and select BALANCE. Turn the main volume knob clockwise for a
right shift or counter-clockwise for a left shift. Exit MENU.
From the Handheld Remote Transmitter
Enter MENU. Scroll to and select BALANCE. Press either volume buttons (+/-) on the
handheld remote transmitter. Each BALANCE key press on the remote transmitter
reduces the gain by 0.5dB on one channel, while increasing the gain on the opposite
channel by the same amount. This results in a detectable shift of the sonic image
towards the desired side.
NOTE: BALANCE ADJUSTMENTS MADE ON ANY INPUT WILL BE APPLIED TO ALL INPUTS AND IS
SAVED EVEN WHEN PREAMPLIFIER IS POWERED DOWN.
RECORD SELECT INPUT ASSIGNMENT
Enter RECORD SELECT MODE by pressing the RECORD pushbutton on the main control
panel, or by selecting RECORD SELECT from the CORUS PREAMPLIFIER’s menu.
Press any input button, ranging from #1 to #6, on the control panel or on the CORUS
PREAMPLIFIER’s remote transmitter to complete the assignment. The selected input
routed to the RECORD-OUT jacks will be confirmed on the left-hand side of the display.
The CORUS PREAMPLIFIER will automatically return to standard operation.
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