JBL CSA-2120 User manual

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2.0 Setup
2.1 Unpacking Your Amplifier
Please unpack and inspect your amplifier for any damage that may have occurred
during transit. If damage is found, notify the transportation company immediately.
Only you can initiate a claim for shipping damage. We will be happy to help
as needed. Save the shipping carton as evidence of damage for the shipper’s
inspection.
We also recommend that you save all packing materials so you will have them if you
ever need to transport the unit. Never ship the unit without the factory pack.
WARNING: Before you start to set up your amplifier, make sure you read and
observe the Important Safety Instructions found at the beginning of this manual.
2.2 Installing Your Amplifier
CAUTION: Before you begin, make sure your amplifier is disconnected from the
power source and all level controls turned completely down (counterclockwise).
To install the amplifier, you can use one of the following approaches:
• Rack mount the amplifier with the rack mounting kit, see Figure 2.2.3 and
Figure 2.2.4.
• Install the amplifer to the wall with the mounting kit, see Figure 2.2.5.
• Stack amps without using a cabinet. For amplifier dimensions, see Figure
2.2.1.
NOTE: When transporting, amplifiers should be supported at front.

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Solution A: Rack Mounting an Amplifier and CST-2120 Transformer Module
To install an amplifier and a CST-2120 transformer module in your cabinet system,
refer to Figure 2.2.3 and follow the steps below:
1. Align two modules side by side, with the front panel towards the same direction.
2. Connect them with the flat bracket.
3. Attach an angle bracket to each side of the amplifier assembly with screws.
4. Install the amplifier assembly into the cabinet. For details of installation in the
chassis of the cabinet, refer to the user guide of your cabinet.
Figure 2.2.1 Dimensions
Figure 2.2.2 Mounting Kit
long angle bracket
flat bracket
angle bracket
Unit: mm [inches]
Figure 2.2.3 Rack mounting an amplifier and CST-2120 Transformer Module

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Solution B: Rack Mounting Single Amplifier
To install single amplifier in your cabinet system, refer to Figure 2.2.4 and follow the
steps below:
1. Attach the long angle bracket to one side of the amplifier that you need to
reserve as dummy module with screws.
2. Attach an angle bracket to the side of the long angle bracket.
3. Attach an angle bracket to another side of the amplifier with screws.
4. Install the amplifier assembly into the cabinet. For details of installation in the
chassis of the cabinet, refer to the user guide of your cabinet.
Solution C: Wall Mounting
To install the amplifier to wall, refer to Figure 2.2.5 and follow the steps below:
1. Attach two angle brackets to both sides of the amplifier with screws.
2. Install the amplifier assembly to a flat and secure position on the wall (for drywall
it is recommended to use #12 x 1-1/2 in. or M6 x 40mm screws into a #12-14 x
1 – ½ in. anchor.) A minimum clearance of 4” should be provided on all sides of
the assembly to allow for heat dissipation.
Figure 2.2.4 Rack Mounting Single Amplifier
Figure 2.2.5 Wall Mounting

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2.3 Ensuring Proper Cooling
When using an equipment rack, mount units directly on top of each other. DO NOT
block side air vents. The back of the rack should be open.
2.4 Choosing Input Wire and Connectors
We recommend using pre-built or professionally wired balanced line (two-conductor
plus shield) 22-24 gauge cables to connect the amplifier balanced input by using
shipped two 3-pin Euroblock connectors, see Figure 2.4. Unbalanced lines may be
used, but may result in hum or RF noise very long cable runs.
You can also use RCA connectors to connect audio devices, for example, CD/DVD
player. However, do not use both Euroblock and RCA audio input connectors on a
single channel at the same time.
NOTE: Custom wiring should only be performed by qualified personnel.
Figure 2.4 Input Wiring
Note: Do not use both Euroblock and RCA audio input connectors on a single
channel at the same time.

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2.5 Output Wiring
To drive distributed speaker systems designed to operate at 70V or 100V, connect
the amplifier to a CST-2120 transformer module with the jumper cable that shipped
with the CST-2120 transformer module, see Figure 2.5.1.
JBL recommends using pre-built or professionally wired, high-quality, two-conductor,
heavy gauge speaker wire. Speakers wires should be twisted cable, if possible. To
prevent the possibility of short-circuits, the wires should be stripped back no greater
than 6 mm (1/4 inch), see Figure 2.5.2.
Suggested below are guidelines to select the appropriate size of wire based on the
distance from amplifier to speaker. Check with local code as this may vary.
Distance Wire Size
Up to 25 ft. (7.6m) 16AWG
26-40 ft. (7.9-12.2m) 14AWG
Figure 2.5.1 Connecting To a CST-2120 Transformer Module
NOTE: If driving a 70V or 100V distributed speaker system, use the optional CST-
2120 transformer module (see Appendix A).
TO
Speaker
TO
Speaker
Figure 2.5.2 Connecting to Speakers

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2.6 Wiring Your Audio System
Typical input and output wirings are shown in Figure 2.6.
INPUTS: Connect input wiring for both channels using either the RCA or the
Euroblock input for each channel.
OUTPUTS: Maintain proper polarity (+/–) on output connectors.
Connect Channel 1 loudspeaker’s positive (+) lead to Channel 1 positive (+) terminal
of amp; repeat for negative (–). Repeat Channel 2 wiring as for Channel 1.
The minimum impedance one of the amplifier channels can drive is 4 Ohms.
Therefore, you can connect up to four 16 Ohms speakers, or two 8 Ohms speakers,
or one 4 Ohms speaker to each amp channel.
Figure 2.6 Wiring Audio System
Professional
audio system
Personal audio
system

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2.7 Connecting to AC Mains
Connect your amplifier to the AC mains power source (power outlet) with the
supplied AC power cord. First, connect the IEC end of the cord set to the IEC
connector on the amplifier; then, plug the other end of the cord set to the AC mains.
WARNING: The third prong of this connector (ground) is an important safety feature.
Do not attempt to disable this ground connection by using an adapter or other
methods.
Amplifiers don’t create energy. The AC mains voltage and current must be sufficient
to deliver the power you expect. You must operate your amplifier from an AC mains
power source with not more than a 10% variation above or below the specified line
voltage and within the specified frequency range indicated on the back panel of the
amplifier. If you are unsure of the output voltage of your AC mains, please consult
your electrician.
2.8 Protecting Your Speakers
It’s wise to avoid clipping the amplifier signal. Not only does clipping sound bad, it
can damage high-frequency drivers. The built-in clip limiter prevents clipping.
Also, avoid sending strong subsonic signals to the amplifier. High-level, low-
frequency signals from breath pops or dropped microphones can blow out drivers.
You can switch on the highpass filters, and this avoids to send subsonic signals
under 70 Hz to the amplifier. Use of the high-pass filter is necessary when using the
CST2120 transformer module to drive a 70V or 100V distributed loudspeaker system
in order to prevent distortion due to transformer saturation.
2.9 Startup Procedure
Use the following procedure when first turning on your amplifier:
1. Turn down the level of your audio source.
2. Turn down the level controls of the amplifier.
3. Power up the amplifier. The Power indicator should light.
4. Turn up the level of your audio source to an optimum level.
5. Turn up the Level controls on the amplifier until the desired loudness or power
level is achieved.
If you ever need to make any wiring or installation changes, don’t forget to
disconnect the power cord.

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3.0 Operation
3.1 Precautions
Your amplifier is protected from internal and external faults, but you should still take
the following precautions for optimum performance and safety:
1. Before use, your amplifier first must be configured for proper operation,
including input and output wiring hookup. Improper wiring can result in serious
operating difficulties.
For information on wiring and configuration, please consult the Setup section of
this manual.
2. Use care when making connections, selecting signal sources and controlling the
output level.
3. Do not short the ground lead of an output cable to the input signal ground. This
may form a ground loop and cause oscillations.
4. WARNING: Never connect the output to a power supply, battery or power main.
Electrical shock may result.
5. Tampering with the circuitry, or making unauthorized circuit changes may be
hazardous and invalidates all agency listings.
6. Do not operate the amplifier with the red Clip LEDs constantly flashing.
7. Do not overdrive the mixer, which will cause clipped signal to be sent to
the amplifier. Such signals will be reproduced with extreme accuracy, and
loudspeaker damage may result.
8. Do not operate the amplifier with less than the rated load impedance. Due to
the amplifier’s output protection, such a configuration may result in premature
clipping and speaker damage.
9. Use the amplifier in a well-ventilated environment and do not use it in ambient
temperature conditions in excess of 40ºC. Failure to do so will result in the auto
disconnection from power supply, and the overheat auto protection function will
be activated. The power indicator will be turned off and there will not be any
audio signal coming out of the amplifier. In this case, turn down the volume to
the minimum, and the amplifier will resume working. When the amplifier returns
to normal temperature then you may turn the volume up to the required level.
10. If the line voltage to the amplifier is too low, the low voltage protection function
will be activated. The power indicator will be turned off.
CAUTION: JBL is not liable for damage that results from overdriving other
system components.

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3.2 Front Panel Controls and Indicators
A. Level: Rotary level control, one per channel.
B. Meter Group (one per channel):
• Clip Indicator: Red LED turns at the threshold of audible distortion.
• Signal Indicator: Green LED flashes when a very low-level signal (Threshold
-40dB) is present at input. May be used for troubleshooting cable runs.
C. Power Indicator: Indicates that AC power is being applied to the unit.
3.3 Rear Panel Controls and Connectors
D. AC Line Connector
E. Output Connectors: 4-pin Euroblock connectors for dual loudspeakers.
F. Amplifier Parameter Switches: Slide DOWN to turn on these functions. Slide UP
to turn them off. The parameter switches are numbered as below:
1. CH1 70Hz highpass filter
2. CH2 70Hz highpass filter
3. CH1 peak limiter
4. CH2 peak limiter
5. Auto-Standby
G. RCA Connectors
H. Euroblock Connectors: Two 3-pin Euroblock connectors each accept a
balanced or unbalanced line-level input signal.
AC
B
D E F G
H
Figure 3.3 Rear View
Figure 3.2 Front View

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Appendix A: Optional Item - Transformer Module
The rack-mountable JBL Commercial®CST-2120 transformer module provides
impedance and voltage matching from the CSA-2120 amplifier to drive 70V and
100V distributed speakers systems.
This unit allows amplifiers without direct 70V or 100V output capability to drive
distributed speaker systems designed to operate at those voltages.
Features
• Provides two channels of impedance matching for “Constant-Voltage” operation
• Provides 70V and 100V output when used with CSA-2120 amplifiers
• Allows the CSA-2120 to be easily integrated into distributed systems
• Detachable Euroblock input and output connectors are included.
CST-2120 Overview
Max Input Power:120 W / CH. 31Vrms (amp rated at 120W @ 8 ohms)
Insertion Loss: < 1dB
Frequency Response: +0/–1 dB (70Hz – 15kHz, at 70 V tap/40 ohms load
or 100 V tap/80 ohms load, 1 watt output)
Dimensions (W x H x D) : 8.2” X 1.7” X 7” (209 mm x 44 mm x 178 mm)
Net Weight: 2.1 Kg (4.6 lbs)
Shipping Weight: 2.5 Kg (5.6 lbs)
Specifications

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Installation
CAUTION: Before you begin, make sure that the amplifier is disconnected from
the power source and all level controls are turned completely down (counter-
clockwise).
1. If you need to mount the transformer module to rack, use a standard 19-inch
(48.3-cm) equipment rack (EIA RS-310B) . You can have the following options
according to your application:
• Rack mounting the transformer module with a CSA-2120 amplifier
• Rack mounting single unit
• Wall mounting
2. Connect the input of the transformer module to the output of the CSA-2120
amplifier with the shipped 4-pin cable.
3. Determine the proper transformer module tap to use, based on the desired
constant-voltage of your system.
CST-2120 Connection

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Output Power (two channels at 1 kHz
power, THD+N<0.5%):
4 Ohms 120 W
8 Ohms 120 W
Frequency Response
(1 watt into 4 or 8 Ohms):
+1/-1 dB
Load Impedance: Rated for 4 or 8 Ohms
Sensitivity (8 Ohms load): 1.4 Vrms
Signal to Noise Ratio (below rated
8-Ohm power at 1 kHz, A weighted):
>100 dB
Crosstalk (Below rated power): >70dB from 20Hz to 1kHz;
>50dB at 20kHz
Input Impedance (nominal): Balanced: 20 k Ohms
Unbalanced: 10 k Ohms
AC Line Voltage and Frequency
Configurations Available:
100-240 V, 50/60 Hz
Maximum Input Signal: +20 dBu typical
Operating Temperature: 0° C to 40° C at 95% relative humidity
(non-condensing)
Auto-Standby: Auto-Standby recovery time: <1ms
Auto-Standby recovery threshold: – 60dBu
Dimensions (W x H x D) : 8.2” x 1.7 x 7” (209 mm x 44 mm x 178 mm)
Net Weight: 1 kg (2.1 lbs)
Shipping Weight: 1.7 kg (3.8 lbs)
Appendix C: AC Power Draw and Thermal Dissipation
Appendix B: Amplifier Specifications

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Appendix D: Contact Information
For additional information, please consult JBL Professional Customer Service, your
system installer or retailer.
On The World Wide Web:
www.jblcommercialproducts.com
Professional Contacts, Outside the USA:
Contact the JBL Professional Distributor in your area. A complete list of JBL Professional
international distributors is provided at our U.S.A. Website: www.jblpro.com

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1.0 Bienvenido
El amplificador CSA-2120 de JBL®es una herramienta profesional diseñada y
construida para aplicaciones de sonido instaladas. El amplificador es un modelo de
dos canales que ofrece una amplificación analógica simple, con una alimentación
universal de modo de interruptor.
El amplificador incluye un kit de montaje en bastidor. Puede adquirirse un módulo
transformador para usarlo en sistemas de sonido distribuido de impedancia alta.
Con el kit de montaje en bastidor, puede instalar el amplificador en un mueble o en
la pared. Si su sistema de altavoces requiere una impedancia alta, el módulo del
transformador puede conectarse entre el amplificador y los sistemas de altavoces
para obtener la impedancia necesaria.
1.1 Características
• Alta potencia de salida, tamaño compacto, peso ligero
• Sonido puro y exacto, con una distorsión muy baja para conseguir lo mejor en
música y voz
• Autoprotección para sobrecalentamientos
• Autoprotección para corriente baja
• Modo de descanso automático
• Entrada y salida Euroblock desmontable
• Alimentación universal con modo de interruptor
1.2 Cómo usar este manual
El presente manual le ofrece la información necesaria para configurar y utilizar de
forma segura y correcta su amplificador. No cubre la totalidad de los aspectos de
la instalación, configuración y funcionamiento que pueden aparecer en cualquier
condición.
Recomendamos encarecidamente que lea todas las instrucciones, advertencias y
avisos contenidos en el presente manual.