DBX 1231

Series 12: dbx's Approach to the Graphic Equalizer for Demanding Sound Reinforcement

Designed for sound reinforcement environments where stability and repeatability are paramount, the Series 12 combines two stereo graphic equalizers: the 1215 with 2 x 15 bands (2/3 octave) and the 1231 with 2 x 31 bands (1/3 octave). Within the lineup, the 1231 is the preferred choice whenever more surgical correction is needed: more bands mean finer adjustment of resonances, feedback, and overall tonal balance without having to "over-correct" too wide an area.

True to professional standards, the 1231 uses ISO standard center frequencies, 45 mm fader travel for immediate reading, and a durable mechanical design. The result: a field-ready tool that is simple to deploy and remains clear and consistent from one system to another.

Who It's For and What It's For: Front of House, Monitors, Fixed Installations, and System Tuning

The dbx 1231 is aimed at sound engineers, contractors, and integrators who need a reliable graphic equalizer to handle unexpected room issues, stabilize wedges, adapt sound reinforcement for an audience, or homogenize an installed system (bar, multipurpose room, place of worship, conference). Its 3U rack format and two channels allow processing of a left/right pair, two monitor mixes, or two separate zones.

The 6 dB / 15 dB gain range switching is particularly useful: at 6 dB, you can fine-tune without altering the overall curve (ideal for light voicing). At 15 dB, you have more headroom to tame stubborn resonances, feedback, or difficult acoustics, while maintaining clear ergonomics thanks to the long-throw faders.

Key Features: Control, Protection, and Integration Without Surprises

Precise and Controlled Correction

With 31 bands per channel at 1/3 octave, the 1231 allows precise targeting of problem areas while maintaining an intuitive and fast approach. The input gain range from -12 dB to +12 dB facilitates level matching within an analog chain, whether as a console insert, between processor and amplifiers, or on a zone matrix.

Bessel Low-Cut Filter: Clean Low End

The switchable 40 Hz Bessel low-cut filter with an 18 dB/octave slope helps control unnecessary sub-bass: stage vibrations, handling noise, ventilation hum, or parasitic energy that unnecessarily stresses amplifiers and speakers. The Bessel response provides a musical and coherent cutoff, useful for securing a system without making it sound "dry."

Comprehensive Connectivity and Noise Management

The 1231 is designed for universal integration: XLR for stage standard, 6.35 mm jacks for some racks or patch bays, and terminal blocks for installations. Balanced inputs/outputs, ground and chassis isolation, and compatibility-focused design reduce the risk of ground noise in complex electrical environments.

Operational Safety: Relay Bypass and Power-Up Delay

To avoid pops and limit audible interruptions, the Series 12 includes a relay bypass on power loss and a 2-second power-up delay. In shared racks (FOH, monitors, zones), these details often make the difference between a smooth performance and chasing unwanted noise.

Audio Performance for Modern Sound Reinforcement

dbx carefully selected components to deliver clean and stable reproduction: wide linear bandwidth, high signal-to-noise ratio, very low distortion, and controlled crosstalk. In practice, this means an equalizer that corrects without "masking" the signal and remains relevant for both speech and amplified music.

Technical specifications