DBX 2231 Dual 31-Band Graphic Equalizer Description

With a prestigious heritage extending back to the heralded 30 Series equalizers, the DBX 2231 Dual 31-Band Graphic Equalizer easily lives up to the referred dbx reputation.

The most revolutionary feature

Besides including two 31-band channels of 1/3-octave equalization, the 2231 empowers you with flexible features like the Peak Plus™ limiter circuit and the amazing Type III™ Noise Reduction system.

exceptional sound, performance, and reliability.

It also includes ±12 dB input gain range; switchable ±6 or ±15 dB boost/cut range; XLR, Barrier strip, and ¼” inputs; nonconductive nylon sliders; and an intuitive user interface with comprehensive output and gain reduction metering. As always, the inevitable result of DBX 2231 Dual 31-Band Graphic Equalizer meticulous attention to detail and top-quality componentry is exceptional sound, performance, and reliability.

Type III™ Noise Reduction system

The most revolutionary feature of the 2231 is the proprietary Type III™ Noise Reduction system, which enables you to boost signal-to-noise ratios by up to an incredible 20 dB. The result of this instant encode/decode process is that you’re no longer forced to employ drastic EQ settings in effort to reduce system noise. Instead, you’re freed to dedicate all EQ bands to the most important thing, the music.

PeakPlus™ limiter technology

Further, the PeakPlus™ limiter technology allows you to easily safeguard your gear against hazardous dynamic surges in program material. In addition to these formidable tools, the 2231’s front panel provides at-a-glance insight as to gain reduction and output level status via its four-stage LED ladders. With such power and finesse built into such a reasonably priced package, it’s easy to see why dbx 20 Series equalizers are relied upon by studio and touring professionals the world over. With such affordable quality, there’s no longer any excuse for compromising sound.

DBX 2231 Dual 31-Band Features

dbx’s revolutionary Type III™ Noise Reduction system, which increases S/N ratio by up to 20 dB
PeakPlus™ limiting technology with threshold range from 0 dBu to +24 dBu (off)
Two 31-band, 1/3-octave channels with switchable boost/cut ranges of ±6 or ±15 dB
±12 dB input gain range
XLR, Barrier strip, and ¼” inputs
4-segment LED ladders for monitoring of gain reduction and output levels—the most comprehensive visual feedback available
Exceptional sound quality
dbx’s unmatched engineering and construction standards

Specifications
Inputs
Connectors	¼” TRS, Female XLR (pin 2 hot), and barrier terminal strip
Type	Electronically balanced/unbalanced, RF filtered
Impedance (bal./unbal.)	40 kΩ / 20 kΩ
Max. Input Level	>+21dBu balanced or unbalanced
CMRR	>40 dB, typically >55 dB at 1 kHz
Outputs
Connector	¼” TRS, Male XLR (pin 2 hot), and barrier terminal strip
Type	Impedance-balanced/unbalanced, RF filtered
Impedance (bal./unbal.)	200 Ω / 100 Ω
Max. Output Level	>+21dBu balanced/unbalanced into 2kΩ or greater >+20dBm balanced/unbalanced (into 600Ω)
System Performance
Bandwidth (±0.5dB)	20 Hz–20 kHz
Frequency Response (+0.5/-3dB)	<10 Hz >50 kHz
Dynamic Range (±15dB/±6dB)	>108 dB / >112 dB
Signal-to-Noise (±15dB/±6dB)	>90 dB / >94 dB
THD+Noise @ 1 kHz	<0.04%, 0.02% typical at +4 dBu
Interchannel Crosstalk (20–20k Hz)	<-80 dB
Noise Reduction	Up to 20dB of dynamic broadband noise reduction
Function Switches
Type III NR	Activates dbx Type III Noise Reduction
EQ Bypass	Bypasses the graphic equalizer section in the signal path
Low Cut	Activates the 40 Hz 18dB/octave Bessel high-pass filter
Range	Selects either ±6 dB or ±15 dB slider boost/cut range
Indicators
Output Level	4-LED bar graph (Green, Green, Yellow, Red) at -10, 0, +10, and +18dBu
Gain Reduction	4-LED bar graph (all Red) at 0, 3, 6, and 10dB
Type III NR Active	1 LED: yellow
EQ Bypass	1 LED: red
Clip	1 LED: red
Low Cut	1 LED: red
±6 dB	1 LED: yellow
±15 dB	1 LED: red
Miscellaneous
Power Requirements	100-230V 50/60 Hz, 23 Watts
Weight	4.81 kg (10.6 lbs)
Dimensions (HxWxD)	13.3 x 48.3 x 20.1 cm (5.25″ x 19.0″ x 7.9″)