dbx DB12V - Active Direct Box

dbx dB12V - Active direct box with 48 V phantom power, 0/20/40 dB pad, and high-cut filter

The dbx dB12V (also known as the dbx dB12 ) is a professional active direct box that converts unbalanced Hi-Z signals (guitar, bass, keyboards, or even speaker outputs ) to a balanced Lo-Z output ready for long, noise-free runs. Its design combines low-noise active circuitry with a custom dbx mu-metal shielded transformer , high-quality Neutrik® connectors, and a rugged, stackable chassis with a rubberized footswitch. It features a switchable 0/20/40 dB pad , a High-Cut filter (6 kHz) for amp inputs with the pad at -40 dB, polarity inversion and ground lift , and a +48 V phantom power LED indicator .

The response and dynamic range have been optimized to preserve the true-to-life characteristics of the source : 20 Hz–20 kHz (+0/−2 dB into a 600 Ω load), typical THD+N 0.003% at 1 kHz , and noise floor −112 dBu . The Hi-Z input offers 1 MΩ with the pad at 0 dB (65 kΩ at −20 dB, 70 kΩ at −40 dB), allowing typical maximum levels of +10/+30/+33 dBu depending on the selected attenuation. All this in a compact format ( 148 × 138 × 56 mm , 0.68 kg ) that withstands intensive use on stage, in the studio, or in a fixed installation.

Main features

• Powered by +48V phantom power and status LED ; low-noise circuitry.
• Mu-metal shielded dbx transformer for isolation and minimal hum.
• Pad 0/20/40 dB for instrument, line and even speaker sources.
• 6 kHz High-Cut filter (only with −40 dB pad) to smooth out power amp inputs.
• Invert (polarity) and Ground Lift to resolve phase and ground loops.
• 1/4" Hi-Z input with 1/4" THRU in parallel to continue feeding your amp.
• Balanced Lo-Z XLR output (Neutrik®) with excellent common rejection (typical CMRR : 106 dB at 60 Hz, 123 dB at 1 kHz).
• Performance : 20 Hz–20 kHz (+0/−2 dB at 600 Ω), THD+N 0.003 % at 1 kHz, noise −112 dBu , dynamic range 122 dB .
• Stackable metal construction , chrome switches and non-slip base.

Product benefits

• Faithful and consistent sound : maintains the punch and character of the instrument with low noise and low distortion.
• Real versatility : from pedals and keyboards to speaker outputs (pad −40 dB + High-Cut) without extra accessories.
• Professional integration : XLR Lo-Z for long runs; THRU for your backline; instant polarity and ground control.
• Tour reliability : rugged chassis, Neutrik® connectors and mu-metal shielded dbx transformer.

Use cases

• Guitar/Bass : DI direct to FOH/monitoring and THRU to the amp; combine with mic and adjust polarity .
• From the amp's speaker output : −40 dB pad + High-Cut (6 kHz). Always maintain the proper amplifier load .
• Keyboards, drum machines and players : normalize impedances, balance and prevent hum with Ground Lift.
• Fixed/AV Installation : Adapts consumer sources to balanced inputs in racks over long distances.

Frequently Asked Questions

• Does it require batteries or an external power supply? No. It runs on +48 V phantom power from the mixer or preamp.
• Can I use it from the speaker output? Yes, with the pad set to −40 dB and the High-Cut filter activated. Always respect the amp's load.
• What does the transformer provide? Galvanic isolation and improved noise/ground rejection without coloring the signal.

Description for projects

dbx dB12V active direct box ; +48 V (< 8 mA) phantom power; 1/4" Hi-Z unbalanced input (RF filtered) with parallel 1/4" THRU ; 0/20/40 dB pad ; active 6 kHz low-pass filter with −40 dB pad; invert (polarity) and ground lift ; input impedances: 1 MΩ (0 dB), 65 kΩ (−20 dB), 70 kΩ (−40 dB); typical max input levels: +10/+30/+33 dBu (0/−20/−40 dB); balanced main output XLR , 600 Ω typical, 106/123/108 dB typical CMRR (60 Hz/1 kHz/10 kHz); Performance: 20 Hz–20 kHz +0/−2 dB (600 Ω), −3 dB 16–30 kHz (600 Ω) / 10–70 kHz (≥ 2 kΩ), THD+N 0.03 % @ 50 Hz 0 dBu / 0.003 % @ 1 kHz 0 dBu, noise −112 dBu , dynamic range 122 dB ; dimensions 148 × 138 × 56 mm ; weight 0.68 kg ; metal chassis with powder-coated finish; dbx mu-metal shielded transformer.