dbx DI4 - 4-Channel Active DI Box - DBX DI4

dbx DI4 - 4-channel active DI box with stereo line mixer and headphone output

The dbx DI4 is a 4-channel active direct box and stereo line mixer in a half-rack size (1U high) . It converts unbalanced instrument and line source signals ( keyboards , samplers, modules, pickup-equipped guitars/basses, recorders) to balanced XLR outputs for your mixer, PA, or interface, while allowing you to create your own stereo monitor mix via RCA and headphone outputs. Each channel features selectable pad , ground lift, and independent level and pan controls for the mix bus, creating a compact solution that replaces four individual DIs and a small line mixer.

Main features

• 4 independent DI boxes in a single chassis (19” half width , 1U).
• Balanced conversion via XLR per channel, plus RCA stereo output from the internal mixer.
• Channel controls : level and pan to the mix bus; 0/−20/−40 dB switchable attenuation ; individual ground lift .
• Headphone output with master control for direct monitoring.
• Audio performance : 20 Hz–20 kHz response (0 to −2 dB) , THD+N 0.0008 % @ +4 dBu/1 kHz, crosstalk < −90 dB.
• 6.35 mm TS jack inputs (high impedance 320 kΩ , input peak +15 dBu ).
• Outputs : Balanced XLR (max. +15 dBu ), RCA (max. +16 dBu ), 1/4” headphones.
• Power supply via external 9 VDC adapter (regional references included); typical consumption 0.775 W.
• Dimensions and weight : 44.5 × 216 × 203 mm (H × W × D approx. from 1.75” × 8.5” × 8”), 1.75 kg .

Product benefits

• Less gear, more control : 4 DI + stereo mixer in one compact unit for stage or studio.
• Ready for demanding signals : −20/−40 dB pads and ground lift per channel to tame high levels and hum.
• Quick operation : adjust level/pan per channel and listen to your mix in headphones without depending on FOH.
• dbx Quality : Ultra-low noise and reduced crosstalk to preserve the character of your instruments.

Connections and controls

• Front : 1/4" TS inputs (4), 0/−20/−40 dB pads (4), ground lift (4), level (4) and pan (4) potentiometers, 1/4" phones with master volume and power LED.
• Rear : 4 balanced XLR (DI outputs), 2 RCA (stereo mixer output), 9 VDC power input.

Use cases

• Keyboardists : Connect multiple keyboards/modules to the DI4 and output 4 XLRs to the stage; create your own mix on RCA/headphones .
• Bass/Guitar + Tracks : A dedicated DI for each source and personal mix for in-ear monitors.
• AV Installation : clean adaptation of power supplies to balanced inputs of mixing consoles/routers.

Frequently Asked Questions

• Can it be phantom powered? No; the DI4 is powered by an external 9 VDC adapter .
• Does the pad have an “off” position? Yes; in addition to −20/−40 dB, the no-attenuation position is equivalent to 0 dB.
• Does the mix bus affect the XLR outputs? No; each XLR output delivers the DI signal for its channel. The stereo mix is ​​output through RCA and headphones .

Description for projects

dbx DI4 active DI box ; 4 independent channels; unbalanced 1/4" TS inputs ( 320 kΩ , peak +15 dBu ); balanced XLR outputs (pin 2 hot, max. +15 dBu , Zout 600 Ω ); stereo line mixer with RCA outputs (max. +16 dBu ); 1/4" headphone output with master control; per-channel controls: level , pan , pad 0/−20/−40 dB , ground lift ; performance: 20 Hz–20 kHz response (0 to −2 dB) , THD+N 0.0008 % @ +4 dBu/1 kHz, crosstalk < −90 dB , DR 129.5 dB(A) ; 9 VDC power supply (external adapter PS0913DC-04 ), consumption 0.775 W ; 19" half-width format (1U), dimensions approx. 44.5 × 216 × 203 mm (H × W × D), weight 1.75 kg .