JBL CSMA 2120 8-Channel 120W Commercial Mixer Amplifier

The JBL CSMA 2120 8-Channel 120W Commercial Mixer Amplifier is a two channel mixer amplifier from JBL's CSMA Family of products.  This mixer/amp features 8 mixer channels. The sharp front panel features volume controls for each channel, a master volume control, adjustable bass and treble rotary controls, and a power switch. Clean and straightforward! No endless lines of buttons and adjusters. The Volume controls are backlit with colored rings to make them visible even when used in dark places. The amplifier can drive 8? and 4? loads, and can also be used with 70V and 100V distributed audio systems without the need for a separate transformer. The JBL CSMA 2120 8-Channel 120W Commercial Mixer Amplifier can be used with the JBL CSR-V in wall volume controls.  (Must be purchased separately).  fThe JBL CSMA 2120 8-Channel 120W Commercial Mixer Amplifier has a built-in universal power supply so it can easily accept AC voltages from 100 to 240 VAC, 50/60Hz. This JBL CSMA 2120 Commercial Series mixer amplifier is manufactured under HARMAN's GreenEdge environmental initiative.  Product materials are made from recycled metals and environmentally-friendly manufacturing processes are used for a greener footprint.

Product Highlights

• More operating efficiency and reliability by using fewer parts. • Significantly reduced power consumption • Greater accuracy and best-in-class signal-to-noise performance. • A proprietary hybrid analog-digital integrated circuit. • Conform to lead-free RoHS standards. • Are lighter in weight leading to less freight and reduced emissions. • Require less power and produce less heat. • Include a low-energy powder coat. • Fanless, space-saving 1U design. • Illuminated rings make them easy to see and operate. • Euro-block type mic/line input connectors and output connectors. • Independent bass and treble controls for each output channel. • Supports 70V and 100V distributed audio systems without needing a separate transformer. • Remote volume control capability using JBL. • CSR-V module and standard Ehternet cable. • Priority muting. • Phantom power. • Configurable output routing. • Universal power supply.  


The JBL CSMA 2120 8-Channel 120W Commercial Mixer Amplifier uses DriveCore technology developed by Crown, another Harman brand. DriveCore technology integrates the amplifier drive stage into the power output stage, and fuses everything into a chip the size of a dime. This significantly reduces the size and weight of the mixer-amps into a 1U rack space.  

Phantom Power

Phantom power (27V) can be applied to all microphone inputs by turning on the Phantom Power switch (one of the unit's DIP switches).  

Hi-Z Switch

The JBL CSMA 2120 8-Channel 120W Commercial Mixer Amplifier is configured to drive low impedance speakers (4 Ohms, minimum). The unit has two DIP switches, one for each amp, that will configure the unit to drive 70V or 100V speaker systems independently and directly. When driving these high impedance speakers, the amplifier automatically inserts a 70Hz high-pass filter.  

Vox Function

Voice-activated ducking, or the VOX function, is available on input channels 1 and 5. This function causes attenuation of the overall output level of the amplifier when the input levels on channels 1 and/or 5 reach a set threshold. A designated trim pot is provided on the two channels for setting the audio input level required to activate ducking. A typical usage of the VOX function is to automatically lower the background music in the room while making announcements over the audio system. After the announcement is made, the background music returns to its previously set level.  

Sleep Mode

 To save energy, the unit is designed to go into sleep mode when no signal is present for approximately 30 minutes. When the input signal returns, the amp will wake up and return to normal operating mode.  

Remote Volume Control

Two RJ-45 ports are provided on the back panel for plugging in up to 2 CSR-V remote volume controllers via Ethernet cables. One RJ-45 port is provided to control the volume for Amp 1, and one port is provided for Amp 2.  

Input & Output

  • dual RJ-45 connectors for use with in-wall volume controls (not included)
  • dual 5-pin Euro-block Priority input connectors (channels 1 and 5) with vocal override for announcements
  • six 3-pin Euro-block connectors with line/mic input switch for balanced input sources
  • six RCA input connectors sum unbalanced stereo inputs to mono
  • 3-pin auxiliary line level output connector for each output channel
  • dual 5-pin Euro-block main outputs compatible with low impedance or constant
  • voltage systems

JBL CSMA 2120 Includes

  • CSMA 240 mixer/amplifier
  • 3' AC power cord (3-prong plug/IEC 3-prong)
  • 4 Self-adhesive rubber feet
  • 2 Front angle brackets
  • 2 Rear flat brackets
  • 2 Rear angle brackets
  • Eight 3-conductor Euro-block connectors
  • Four 5-conductor Euro-block connectors
  • 10 M4 x 20mm Phillips-head rack-mounting screws (each with a flat washer)
  • Three 3/16" screws
  • 3 Flat washers
  • 3 Split lock washers
  • 12 M3 x 5mm flat-head screws
  • Operation Manual


Maximum Output Power 120 W per channel into 4 ? or 8 ?, 1 kHz, ? 0.5% THD
Insertion Loss 1 dB maximum
Continuous Power 15 W per channel
Number of Channels Input: 8 Output: 2
Line Output Level 5.0 V RMS into 10 k?
Input Sensitivity Mic Input: 3 mV RMS Line Input: 775 mV RMS RCA Input: 300 mV RMS 1
Please Note:
To obtain full rated power at 8 ? (or 5 VRMS to line output) close
Frequency Response 4/8 ? Output: 20 Hz - 20 kHz, ±2 dB 70 V/100 V Outputs: 80 Hz - 15 kHz ±2 dB Line Output: 20 Hz - 20 kHz, ±1 dB 2
Please Note:
Measured at 2.83 V RMS into rated load impedance at any output close
Total Harmonic Distortion (THD) Power Amplifier Output: <0.5%, 20 Hz - 20 kHz Line Output: 0.05% typical 3
Please Note:
Measured at 2.83 V RMS into rated load impedance at any output close
Signal to Noise Ratio > 90 dB
Nominal Input Impedance Mic: 400 ? Line: 20 k? (balanced) RCA: 50 k?
Minimum Load Impedance Low Impedance Output: 4 ? 70 V Output: 40 ? 100 V Output: 80 ?
Crosstalk -70 dB @ 1 kHz
Operating Temperature / Humidity 32 to 95°F (0 to 35°C), 95% RH (non-condensing)
Storage Temperature -4 to 185°F (-20 to 85°C)
Phantom Power 27 VDC
AC Input 100-240 VAC, 50/60 Hz
Dimensions (W x D x H) 17.2 x 11.9 x 1.7" (43.7 x 30.3 x 4.3 cm)
Weight Approximately 12.1 lb (5.5 kg)