The dbx12 Series were designed to meet the needs of the most demanding sound reinforcement environments, while offering the simplicity of straightforward controls. The 1231 provides standard features like dual-channels, 31 1/3 octave bands, ISO frequency centers, +/- 12 dB input gain range, and switchable 40Hz/18 dB per octave low-cut filters, but also includes other insightful features. These include 45 mm faders; selectable +/-6dB or +/-15dB boost/cut range for precise gain adjustments; XLR, barrier strip, and 1/4 in. TRS connectors for installation ease; balanced inputs and outputs for quiet operation; and chassis/signal ground lift capabilities for quick hum isolation. The visionary design of the dbx 12 Series makes your job easier.

The dbx12 Series Equalizers were precision engineered to provide years of maintenance-free operation in any application. The magnetically isolated transformer, electronically balanced/unbalanced inputs and servo balanced/unbalanced outputs, RF-filtered inputs and outputs, and power-off hard-wire relay bypass with 2 second power up delay were steps our engineers took to ensure compatibility for all installations. Only the best components were utilized, yielding a 10Hz to 50kHz frequency response, greater than 90dB SNR (ref +4dBu), less than 0.005% THD +Noise (1kHz at +4dBu), and interchannel crosstalk of less than -80dB from 20Hz to 20kHz. All this attention to detail is contained in a 3U steel/aluminum chassis. It's no wonder that dbx has been a leader in the industry for over 25 years.

Features:
Switchable Boost/Cut range between ±6dB and ±15dB

Electronically balanced/unbalanced inputs

Servo balanced/unbalanced outputs

RF filtered inputs and outputs

XLR, Barrier Strip, and 1/4 in. TRS connectors

-12dB/+12dB input gain range

18dB/octave 40Hz Bessel low-cut filter

Chassis/signal ground lift capability

Internal power supply transformer

Power-off hardwire relay bypass with 2-second power-up delay

Technical Info

Inputs
Connectors: 1/4 in. TRS, female XLR (pin 2 hot), and barrier terminal strip 
Type: Electronically balanced/unbalanced, RF filtered 
Impedance: Balanced 40k ohm, unbalanced 20k ohm 
Max Input Level: >+21dBu balanced or unbalanced 
CMRR: >40dB, typically >55dB at 1kHz 

Outputs
Connectors: 1/4 in. TRS, male XLR (pin 2 hot), and barrier terminal strip 
Type: Impedance-balanced/unbalanced, RF filtered 
Impedance: Balanced 200 ohm, unbalanced 100 ohm 
Max Output Level: >+21dBu balanced/unbalanced into 2k ohm or greater 
>+18dBm balanced/unbalanced (into 600 ohm) 

System Performance
Bandwidth: 20Hz to 20kHz, +0.5/-1dB 
Frequency Response: <10Hz to >50kHz, +0.5/-3dB +/-15dB range +/-6dB range 
Dynamic Range: 109dB 115 dB 
Signal-to-Noise: 90 dB 97dB 
THD+Noise: <0.005% 

Function Switches
EQ Bypass: Bypasses the graphic equalizer section in the signal path 
Low Cut (recessed): Activates the 40Hz 18dB/octave Bessel high-pass filter 
Range (recessed): Selects either +/- 6dB or +/- 15dB slider boost/cut range 

Indicators
Output Level Meter: 4-LED bar graph (Green, Green, Yellow, Red) at -10, 0, +10, and +18dBu 
EQ Bypass: 1 LED: Red 
Clip: 1 LED: Red 
Low Cut: 1 LED: Red 
+/-6dB: 1 LED: Yellow 
+/-15dB: 1 LED: Red 

Power Supply
Operating Voltage: 100VAC 50/60Hz, 120VAC 60Hz 
230VAC 50/60Hz 
Power Consumption: 24W 
Mains Connection: IEC receptacle 

Physical
Dimensions: H X W X D 8.9cm x 48.3cm x 20.1cm 
Weight: 3.9 kg 
Shipping Weight: 4.3 kg