C-540 , C-8120 and C-8240 Commercial Mixer/Amplifiers Owner`s

Premium Residential & Commercial Audio/Video Products
C-540 , C-8120 and C-8240
Commercial Mixer/Amplifiers
Owner's Manual
Immediately upon receipt, inspect the unit and shipping container for indications of improper
handling or in-transit damage. This equipment was carefully inspected and tested before leaving
the factory. Notify the Transportation Company, Wholesaler or Retailer immediately if any
damage is found. Be sure to save the carton and packing material as evidence of damage for
later inspection. DO NOT SHIP the unit back to the factory unless authorized to do so by the
• Read and keep these instructions.
• Heed all warnings and follow all instructions contained within this manual.
• Do not use this unit near water.
• Clean only with dry cloth.
• Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions.
• Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including
amplifiers) that produce heat.
• Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades
with one wider than the other. A grounding type plug has two blades and a third grounding prong. The wide
blade or the third prong are provided for your safety. If the provided plug does not fit into your outlet,
consult an electrician for replacement of the obsolete outlet.
• Protect the power cord from being walked on or pinched particularly at plugs, convenience receptacles, and
the point where they exit from the apparatus.
• Only use attachments/accessories specified by the manufacturer.
• Unplug this apparatus during lightning storms or when unused for long periods of time.
• Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been
damaged in any way, such as when the power-supply cord or plug is damaged, liquid has been spilled or
objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate
normally, or has been dropped.
• Operate the product only with the voltage specified on the unit. Fire and/or electric shock may result if a
higher voltage is used.
• Do not modify, kink, or cut the power cord. Do not place the power cord in close proximity to heaters and
do not place heavy objects on the power cord and/or the product itself, doing so may result in fire or
electrical shock.
• Replace the protective cover over the speaker terminals after installation. Do not touch the 70V speaker
terminals as electric shock may result.
• Ensure that the safety ground terminal is connected to a proper ground. Never connect the ground to a gas
pipe, as a severe explosion and/or fire may result.
• Be sure the installation of this product is stable, avoid slanted surfaces as the product may fall and cause
injury, property damage, electrocution and/or fire.
Congratulations and thank you for purchasing a Sound Acoustics product. The Sound Acoustics “C”
series amplifiers are designed and built to provide ultra reliable performance for professional
background music and paging applications. All Sound Acoustics amplifiers feature color coded
inputs and outputs, ultra low noise components, front panel auxiliary inputs and PRO-RVC remote
control inputs. Sound Acoustics inputs are very flexible and will accept practically any source and
source level. This frees the installer to design the system to suit the customers needs exactly.
Please read this entire manual to get the most from your Sound Acoustics product.
Front Panel Operation and Connections
Inputs 1-5 (Inputs 1-2 C-540) - These control the level of each channel in the overall mix. A
good level to start off with is the 12:00 position then adjust as needed.
Input 6 (Input 3 C-540) - This input controls the level of input 6 (input 3 C-540) in the overall
mix. This also controls the level of the front panel Mp3 input. NOTE: Input 6 (input 3 C-540) also
feeds the Music On Hold “MOH” output which will be explained in detail on page _________later in
this manual.
Bass - The bass control is a shelving type equalizer that boosts or cuts bass frequencies at 100Hz
+/- 12 dB. The center “0” position does not affect the signal. Equalizers should be used sparingly.
Too much boost can cause feedback when using microphones.
Treble - The Treble control is a shelving type equalizer that boosts or cuts bass frequencies at
10kHz +/- 12 dB. The center “0” position does not affect the signal. Equalizers should be used
sparingly. Too much boost can cause feedback when using microphones.
Master - The Master gain control controls the overall output of the amplifier. Pay close attention
to the output LED's. Signal, -3dB and OL. The LED's monitor the output level and provide visual
feedback. It is common to have the signal and -3dB LED's lit. When the OL “RED” LED is lit or
flashing the amplifier is being overloaded. Immediately turn down the Master volume control. Readjust Input level controls 1-6 to the desired mix and then adjust the Master level control to the
desired volume.
NOTE: When using the PRO-RVC remote control, set the amplifier master volume to 75% then
control the master volume remotely from the PRO-RVC.
Power - The Power switch applies power to the amplifier. The Power switch is also part of the
protection circuitry of the amplifier. If the amplifier is overloaded it will automatically shut down to
protect the circuitry from damage. If this occurs turn the power switch off, turn the master
volume down, wait 15 seconds, then turn the Power switch on. The amplifier should return to
normal operation. If the amplifier continues to shut down automatically check the troubleshooting
guide on page _________ of this manual.
Signal - The Signal LED lights when a signal is present in the master bus output. With a source
connected to one of the inputs and the input level turned up to 12:00 turn the Master volume up
slowly until the Signal LED lights. With a valid source playing it is normal for the Signal LED to be
lit solidly.
-3dB LED - The -3dB LED lights when the signal in the master bus output is 3dB below clipping.
This allows the user to adjust levels to prevent clipping and overloading the amplifier.
OL LED - The OL LED is the overload warning light. When the OL LED flashes occasionally it is
indicating occasional peaks in the output signal. If the OL LED lights solidly the amplifier is being
overdriven. Immediately reduce the input levels and the Master volume control until the OL LED is
not illuminated. Occasional flashing is normal.
MP3 Input - The Mp3 input is a stereo 3.5mm 1/8” jack that will accept signals from practically
any device with a headphone output jack. Mp3 players, iPod's, portable phones, computers,
receivers etc. The Mp3 Input also feeds the music on hold MOH outputs. If a source is connected
to the rear panel Input 6 jacks the Mp3 input will automatically override that source when a
connector is inserted. It is possible to have two output zones with different sources being
broadcast simultaneously by using the Mp3 input or rear panel Input 6 jacks as the source for the
MOH output and using any other input as the source for the main outputs. The Mp3 jack is a quick
way to connect to the amplifier without needing access to the back panel.
Note: All front panel knobs are removable and can be replaced with the included non-adjustable
security covers.
Rear Panel Operation and Connections.
NOTE: Rear Panel color coding
GREEN = Input
RED = Output
Inputs 1-2 (Input 1 C-540) - Inputs 1 &2 are priority inputs. These inputs function the same as
the other input channels but offer some added features suitable for paging microphones. Priority
means “override”. Simply stated the microphone or line level signal will override all other inputs.
Rear Panel Connections and dip switches:
RCA - These jacks accept line level signals from CD's, DVD's, Tuners etc. This is an unbalanced
input that sums the signal to mono. The INPUT LEVEL knob does not affect the RCA input level.
EURO BALANCED - This is a balanced three pin detachable connector that will accept
microphone or line level sources. You can also connect an unbalanced source by connecting the
HOT to + and connecting the COLD or (return) to – and attaching a jumper to – and G. The INPUT
LEVEL control affects the input level for the EURO input jack.
INPUT LEVEL – This rotary control adjusts the input level for the EURO connector only. Use this
to match the correct input level based on the signal strength of the device connected. A good
starting point is the 12:00 position. If you hear distortion turn the control counter clockwise. Turn
this control clockwise to increase the input level.
VOX SENS – This rotary control adjusts the sensitivity of the override circuit. Turning this control
clockwise triggers the auto sensing circuit sooner. This control will function only when the
PRIORITY #4 dip switch is ON. Start at the 12:00 position, If the override cuts in and out when
there is no page signal present (called false triggering) then reduce the SENS by turning counter
clockwise. If the leading edge of the page is cut off increase the sensitivity by turning the SENS
control clockwise.
DIP SWITCH 1 48v PHT – This switch applies 24v to the + and – pins of the EURO BALANCED
jack. This feature provides phantom power for condenser microphones. NOTE: always set the 48v
PHT dip switch UP or OFF if a line level source or dynamic microphone source is connected where
phantom power is not needed.
DIP SWITCH 2 MIC/LINE – This switch adjusts the sensitivity of the EURO BALANCED jack
between microphone level signals and line level signals. Set the switch up for line level and down
for microphones. Note: line level sources will overload the EURO BALANCED input if the dip switch
is set to MIC. If the dip switch is set to LINE and a microphone is connected the input level will be
too low. Always make sure this dip switch is set appropriately for the device that is connected.
DIP SWITCH 3 100Hz HPF - With this switch ON all frequencies below 100Hz will be cut at 18dB
per octave. Use this switch with microphones to roll off unwanted low frequency rumbles and
minimize pops from mouth noises.
DIP SWITCH 4 PRIORITY – With this switch ON the source connected to the EURO BALANCED
connector will override all other inputs. This is commonly used for paging microphones where the
background music source would be connected to one of the inputs 3-6 and a paging microphone
would be connected to input 1 or 2. When the microphone signal is broadcast the back ground
music source will automatically mute and then return to normal after the broadcast is complete.
INPUTS 3-5 (INPUT 2 C-540) The remaining inputs function exactly the same as inputs 1 & 2
except they do not have VOX SENS, 100Hz HPF, and Priority.
It is still possible to connect a microphone or a line level source to any input. This provides the
ultimate flexibility.
INPUT 6 (INPUT 3 C-540) These inputs have multiple functions. They can operate the same as
all the other inputs to feed the main outputs and they also feed the music on hold MOH outputs.
When using the music on hold MOH outputs connect your music source or store caster input here.
The dual RCA jacks and the EURO BALANCED jacks can feed the music on hold MOH outputs.
NOTE: The front panel Mp3 jack can also be used to feed the music on hold MOH outputs. When a
source is plugged into the front panel Mp3 jack it will automatically override the source plugged
into the input 6 (or input 3 C-540) RCA jacks. If the front panel volume knob is turned up this
input will broadcast on the main outputs as well as the MOH output. Effectively you can create two
output zones with different sources. Please see the music on hold MOH section for more
PRE OUT – This RCA jack is an unbalanced pre-amp output (post tone controls) that can be used
to connect to other amplifiers or external audio devices. The PRE OUT jack and the AMP IN jack
can be used to create and effects loop to feed an external equalizer or feedback eliminator. Take
the PRE OUT to the input of the external device and take the output of the external device to the
AMP IN jack to create the loop.
AMP IN - The AMP In jack can be used to amplify signals from another mixer or external device.
The internal pre-amp section is overridden when a jack is connected to AMP IN. This can be used
to convert the C-8120/8240/540 into a slave amplifier or used as an effects loop as described
above in the PRE OUT section.
TEL INPUT – This is a balanced audio input that is designed to accept signals from an analog
telephone output. Due to the varied output levels from different telephone systems we have
provided a level control that allows precise level adjustments.
NOTE: The TEL INPUT automatically overrides all signals in the pre-amplifier and broadcasts the
page when an announcement is made through the telephone system.
NOTE: Some telephone systems carry noise and DC voltages on their outputs. We recommend
using the optional SA-TEL1 isolation transformer between the phone output and the TEL INPUT to
eliminate these problems.
Most phone systems provide a balanced tip & ring audio output that can be connected to the +
and – terminals on the EURO input jack.
CHIME - The CHIME contacts can be used as a pre-announce tone for paging or as an alert tone
for doorbells, telephones, etc. Simply short the contacts with a switch from a microphone or
external contact closure and the chime tone will broadcast. We have provided a CHIME LEVEL
control to set the precise volume level desired.
MUTE – The MUTE contacts can be used to instantly mute background music sources for
immediate paging or emergency situations. Simply short the MUTE contacts with a switch or
external contact closure and all inputs will mute with the exception of the PRIORITY inputs.
PRIORITY inputs will function as normal provided the PRIORITY function is ON. NOTE: When using
the PRO-RVC for a remote music input it is recommended to short the mute contacts. The PRORVC will override other music sources that may be connected to the amplifier.
MOH OUT - The MOH music on hold output offers two output levels. 1.) 600 ohm 1v balanced
which is used to drive line level music on hold inputs. 2.) 8 ohm 1 watt which is used to drive
phone systems that require more input gain. This output can also be used to power an 8 ohm
loudspeaker. The MOH output can also be used as a Zone 2 output. Input 6 (input 3 C-540) and
the front panel Mp3 input signals are fed to the MOH output. All other inputs are fed to the main
outputs. It is possible to have two completely different sources broadcasting simultaneously by
using the MOH output to feed another amplifier or 8 ohm speaker and the main outputs to feed
another group of speakers.
BRIDGING INPUT/OUTPUT – (C8120 & C8240 ONLY) Many installations require flexibility
where multiple amplifiers need to be combined for large room activities and then separated for
smaller multiple room activities. This is referred to as room combining. Sound Acoustics amplifiers
offer this feature with simple easy to use bridging terminals. These terminals provide a way to
send and receive balanced line level audio from the internal mixer of the C-8120 or C8240. The
bridging terminals balanced signal can be sent long distances without introducing noise or
interference using 22 AWG or 24 AWG shielded two conductor stranded copper wire.
Connect the bridging + / -- / G terminals of one Sound Acoustics amplifier to the same terminals
on another Sound Acoustics amplifier. The amplifiers will operate independently until the SEL
contacts are shorted.
SEL CONTACTS (C8120 & C8240 ONLY) - Shorting the SEL terminals using a switch or
external contact closure will combine the pre-amp signals in both the amplifiers. The amplifiers
will operate as one larger amplifier. It is possible to connect multiple amplifiers to create a room
combining system. When connecting multiple amplifiers together you may need to adjust the
volume levels on the individual amplifiers to create a well balanced mix.
NOTE: To combine two or more amplifiers the SEL contacts must be shorted on each amplifier you
wish to combine.
EXAMPLE: Connect the bridge terminals of amp 1 to amp 2. Short the SEL contacts on amp 1.
The amps will not combine. Short the SEL contacts on both amps 1 & 2 and the amps will
combine. Any source that is connected to either amp will broadcast on both amps.
REMOTE MASTER VOLUME (C8120 & C8240 ONLY) - All Sound Acoustics amplifiers have the
ability to control the master volume remotely through the PRO-RVC input. More about this is the
next section. The C-8120 and C-8240 provide an additional remote master volume control input
that can be controlled remotely from a 10kohm potentiometer. Set the maximum volume level
desired with the front panel master volume control and connect a 10Kohm potentiometer to the
REMOTE MASTER VOLUME contacts. The potentiometer will act as an attenuator, controlling the
master volume of the amplifiers remotely.
PRO-RVC - All Sound Acoustics amplifiers provide the unique PRO-RVC input. This is an RJ45
female jack that allows the connection of up to three PRO-RVC remote microphone/line mixers.
This feature can provide up to 6 additional inputs (3 microphone & 3 line level) with individual
volume control plus remote master volume control to any Sound
Acoustics amplifier. The PRO-RVC connects with Cat5 cable
providing one RJ45 input and one RJ45 output for daisy chaining
up to three PRO-RVC's to each amplifier. Power for the PRO-RVC
is provided by the amplifier and additional power supplies are
not necessary. When using using the PRO-RVC short the MUTE
contacts if you want the PRO-RVC to maintain constant priority
over other inputs connected to the amplifier. The PRO-RVC input
provides a PRIORITY switch. Set the PRIORITY switch to ON for
momentary override of other sources connected to the amplifier.
Please read the PRO-RVC installation guide included with the
It is possible to use the PRO-RVC with other amplifier brands as a stand alone remote mic/line
mixer by installing the optional RVC-ADAPT. Consult your authorized Sound Acoustics dealer for
more information.
SPEAKER OUTPUTS - Sound Acoustics amplifiers provide 4 speaker level outputs. Do not use
more than one output at a time. This could overload the amplifier.
Remove the EURO style connector and select from the following chart.
– Common or negative -4 ohm – Connect to a direct coupled loudspeaker (no transformer) min impedance 4 ohms
- Connect to 25V transformer coupled loudspeakers.
70V - Connect to 70V transformer coupled loudspeakers
100V - Connect to 100V transformer coupled loudspeakers
Always use good quality stranded copper wire.
Speaker outputs
4 ohm 12-16 AWG stranded copper unshielded
16-18 AWG stranded copper unshielded
16-18 AWG stranded copper unshielded
16-18 AWG stranded copper unshielded
CAUTION: Keep the speaker output guard on at all times. This will help prevent shock and fire
hazards. Ensure the power cord is not connected to the AC outlet when making connections.
POWER CORD - Connect the AC power cord to 120V AC outlets only. Do not connect the power
cord until all audio connections are made. Serious damage may result if the amplifier is connected
to line voltages other than 120V AC.
FUSE - TYPE T6, 3al/250V - Always use the correct fuse for replacement. Failure to use the
correct fuse or shorting the fuse could result in fire and serious damage.
Output Power RMS
40 watts
120 watts
240 watts
Frequency Response
40Hz- 20kHz
40Hz- 20kHz
40Hz- 20kHz
Total Harmonic Distortion
0.5% at rated power
0.5% at rated power
0.5% at rated
Signal To Noise Ratio Mic
Signal to Noise Ratio Line
Signal to Noise Ratio Tel
Inputs Microphone
3 expandable to 6
6 expandable to 9
6 expandable to 9
Inputs Line Level
5 expandable to 8
9 expandable to 12
9 expandable to 12
Inputs Telephone
Chime with level adjust
Speaker Outputs
Line level Outputs
1 Balanced
1 Balanced
Signal to Noise Ratio
Bridging In/Out
MOH Output
8ohm 1W & 600 ohm
8ohm 1W & 600 ohm 8ohm 1W & 600
ohm 1V
Remote Master Volume
10Kohm Pot & PRORVC
10Kohm Pot & PRORVC
Power Requirements AC
Power Consumption AC
8.5”W x 4”H x 11.25”D 17”W x 4” H x 14”D
17”W x 4” H x 14”D
Optional Accessories 1
Rack Kit SA-RK2.5
Rack Kit SA-RK2.0
Rack Kit SA-RK2.0
Optional Accessories 2
Optional Accessories 3
SA-TEL1 600 ohm
telephone isolation
SA-TEL1 600 ohm
telephone isolation
SA-TEL1 600 ohm
telephone isolation
Shipping Weight
Contact Information
Sound Acoustics HQ
1360 Frances Street
Vancouver BC Canada V5L 1Y9
E-mail: info@mysoundacoustics.com
Website: www.mysoundacoustics.com
Sound Acoustics commercial amplifiers are warranted to be free from defects in workmanship and
materials for a period of three (3) years without charge for parts or labour. The warranty applies
only to the original owner. The owner’s responsibilities are to provide proof of purchase and
transportation to the dealer the unit was purchased from or transportation to the Sound Acoustics
factory. This warranty does not apply to units which have been subject to misuse, abuse, neglect
or improper installation, and does not apply to repairs or alterations by unauthorized personnel.
This warranty specifically excludes responsibility for consequential damage.
Retention of your dated ORIGINAL BILL OF SALE is required to obtain service under the terms of
the warranty.
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