R-Series
R275HC
2-Channel
Power Amplifier
User’s Manual
Download from Www.Somanuals.com. All Manuals Search And Download.
R275HC AMPLIFIER
INTRODUCTION
The Russound R275HC is a 2-channel high-current power
amplifier capable of driving low impedance loads and
incorporates selectable volume control protection circuitry.
The R275HC is rated at 75 watts per channel into 8
ohms and 100 watts into 4 ohms. With the
Stereo/Bridge Mono switch in the Bridge Mono position,
both amplifier channels are combined for a higher pow-
ered mono output. In Bridge mode the R275HC is rated
at 200 watts of power into a single 8-ohm load. All this
power is backed by a high output toroidal transformer.
Each amplifier output channel incorporates robust pro-
tection circuitry for safety and reliability under extreme
circumstances.
This amplifier can be used for power upgrades in specif-
ic zones, for large speaker selector or volume control
systems and for long series-parallel speaker runs
(e.g., large outdoor zones).
FRONT PANEL
1
Tri-color Indicator LED: The LED will illuminate red when the power is on and the amplifier is in standby,
green when the amplifier is active and orange when in short circuit protection.
1
RACK MOUNTING
The R275HC amplifier can be rack mounted using the included rack-mount ears and hardware to attach the ears to
the amplifier. The amplifier will take 2 rack spaces with the feet removed.
R275HC Side View
Rack Ear
Screw Holes
Rack Ear
Rack Ear
Side View
Front View
3
Download from Www.Somanuals.com. All Manuals Search And Download.
R275HC AMPLIFIER
1
2
3
4
3
7
8
5
5
6
6
7
Power Switch: Turns the amplifier on/off. This
switch does not disconnect the main power feed
from the amplifier; this requires that the power cord
be unplugged from the outlet.
Stereo/Bridge Mono Switch: Sets the pair of
amplifier channels for stereo or bridge mono opera-
tion.
1
2
Line Input: The line audio input is a sensing input
that will activate the amplifier when an audio signal
from a source is present. When there is no audio
the zone will go into standby. The Left input is used
for bridged mono operation only.
Low Cut (High Pass) Switch: Enables/disables the
filter that reduces very low frequency energy and
protects autoformer-based volume control/speaker
selectors. When “on,” the filter is set to -3dB at 40
Hz. When off, the frequency response is flat from
20Hz to 20kHz.
8
AC Input: The AC voltage input for the North
American model is 120VAC at 60Hz (for the
European model, 230VAC at 50Hz). This receptacle
accepts a 3-prong IEC 320 type connector. A
detachable 3-terminal power cord is included.
3
4
Gain Controls: Left and Right gain controls inde-
pendently adjust the sound level for each channel.
When used in the bridged mode only the Left control
is used.
Loop Output: The loop output is a passive
passthrough of the line input. These jacks can be
used to daisy chain the input signal to another
amplifier in the system.
5
Speaker A/B Outputs: The A and B speaker out-
puts are in parallel to the amplifier output. The mini-
mum load in stereo mode is 4 ohms. This can be
used to drive up to 2 pairs of 8-ohm speakers or 1
pair of 4-ohm speakers. The minimum load imped-
ance for bridged mode operation is 8 ohms,
Speaker B only.
4
Download from Www.Somanuals.com. All Manuals Search And Download.
R275HC AMPLIFIER
BRIDGED OPERATION
Following the Bridge mode markings in red on the back
of the amplifier: Connect the negative lead (-) of the
speaker cable to the R+ terminal. Connect the positive
lead (+) of the speaker cable to the L+ terminal. Set the
Stereo/Bridge Mono switch to Bridge Mono, connect the
Line In feed from a source to the Left Line In connection
and restore power to the amplifier.
When the amplifier is in Bridged mode operation, both
the left and right channels are combined for a higher
power mono output.
For bridged amplifier operation, turn off the power to the
amplifier and connect an 8-ohm minimum load to the
Speaker B output.
(+)Positive
(-)Negative
Audio RCA Cable from source
Speaker
cable
8-ohm Speaker
THERMAL PROTECTION
PROTECTION CIRCUITRY
All Russound amplifiers are designed with special circuit-
ry to safeguard the amplifier under a thermal overload
condition. Thermal protection mode can only engage
when the unit has been run at high volume for extended
periods of time without adequate ventilation and/or when
speaker impedances are below the minimum levels for
the amplifier. If this fault occurs, turn off the amplifier,
and check that the speaker impedance rating is above
the minimum rating. Also check for adequate ventilation
around the amplifier and make adjustments if necessary.
Once the unit has cooled to safe operating tempera-
tures, the amplifier may be powered back on.
All Russound amplifiers are designed with special circuit-
ry to safeguard the amplifier under a short-circuit condi-
tion. A faulty speaker can also cause a short circuit con-
dition.
The front panel LED illuminates orange when the amplifi-
er is in short circuit protection. If this fault condition
occurs, turn off the amplifier and check speakers for
short circuit conditions when appropriate.
5
Download from Www.Somanuals.com. All Manuals Search And Download.
R275HC AMPLIFIER
POSSIBLE SYSTEM CONFIGURATIONS
enables a filter that reduces the low frequency energy
which protects the volume controls/speaker selectors
and increases the efficiency of the system.
The R275HC can be configured for large autoformer-
based volume control systems/speaker selectors. When
using the R275HC for this application, set the Low Cut
switch to the “On” position. Turning this filter “on”
Line out from Source
Low Cut switch
in “On”position
S P E A K E R S
S P E A K E R S
S P E A K E R S
S P E A K E R S
EZB-1SC Modular
Autoformer-based
Connecting Block
volume control
RUSSOUND
SPEAKERS
SPEAKERS
SPEAKERS
SPEAKERS
8-ohm Speaker
The R275HC can also be configured as a power upgrade for specific zones, for use with large speaker selectors and
for long series-parallel speaker runs (e.g., outdoor zones).
CAM6.6
RCA Cable
CAM6.6T Controller
R275HC Amplifier
Speaker Cable
8-ohm Speaker
Speaker Cable
8-ohm Speaker
6
Download from Www.Somanuals.com. All Manuals Search And Download.
R275HC AMPLIFIER
SPECIFICATIONS
Stereo Continuous Output Power: 75W per channel at 8 ohms
100W per channel at 4 ohms
Bridged Output Power: 200W at 8 ohms, 2 channels bridged
THD+N: <0.05% from 20Hz to 20kHz
Signal-to-Noise Ratio: >100dB A-weighted
Frequency Response: 20Hz to 20KHz +/- 0.3dB
Input Sensitivity: 70mV for 1W at 8 ohms
610mV for 75W at 8 ohms
Input Impedance: 47kohms Line Input
Voltage Gain: 32dB
Power Requirements: North American Model:
120VAC 60Hz 2.5A
IEC 320 type connector with 3 terminal detachable power cord.
Power Requirements: European Model:
230VAC 50Hz 1.2A
IEC 320 type connector with 3 terminal detachable power cord.
Dimensions: 17" W x 14"D x 4.125"H (43 x 35.5 x 10.5 cm)
Weight: 20.3lbs. (9.2kg)
WARRANTY
The Russound R275HC is fully guaranteed for two (2) years from the date of purchase against all defects in materials
and workmanship. During this period Russound will replace any defective parts and correct any defect in workman-
ship without charge for either parts or labor. For this warranty to apply, the unit must be installed and used according
to its written instructions. If service is necessary, it must be performed by Russound. The unit must be returned to
Russound at the owners expense and with prior written permission. Accidental damage and shipping damage are not
considered defects under the terms of the warranty. Russound assumes no responsibility for defects resulting from
abuse or servicing performed by an agency or person not specifically authorized in writing by Russound. Damage to
or destruction of components due to improper use voids the warranty. In these cases the repair will be made at the
owners expense. To return for repairs, the unit must be shipped to Russound at the owners expense, along with a
note explaining the nature of the service required. Be sure to pack in a corrugated container with at least 3 inches of
resilient material to protect the unit from damage in transit.
Russound sells products only through authorized Dealers and Distributors to ensure that customers obtain proper
support and service. Any Russound product purchased from an unauthorized dealer or source, including retailers,
mail order sellers and online sellers will not be honored or serviced under existing Russound warranty policy. Any sale
of products by an unauthorized source or other manner not authorized by Russound shall void the warranty on the
applicable product.
7
Download from Www.Somanuals.com. All Manuals Search And Download.
R-Series
R275HC
2-Channel
Power Amplifier
User’s Manual
5 Forbes Rd. Newmarket, NH 03857, USA
Tel 603.659.5170 • Fax 603.659.5388
e-mail: [email protected]
28-1167
03/22/05
Download from Www.Somanuals.com. All Manuals Search And Download.
|