What is a DI box?
Bass, keys, acoustic guitar or playback often go through a DI box. Here is, in plain language, what a DI does and when you use one.
What is a DI box?
A DI box (direct injection) converts an unbalanced, high-impedance instrument signal into a balanced, low-impedance signal the mixing console can handle cleanly over an XLR cable. In short: it turns an instrument signal into a “mic-friendly” one, without noise or loss over long cable runs.
Active or passive?
A passive DI needs no power and is fine for strong signals like an active bass or keyboard. An active DI needs power (battery or 48V) and works better with weak, high-impedance sources like a passive bass or an acoustic guitar with a piezo pickup.
What do you use a DI for?
- Bass you want to tap directly, with or without a mic on the cab.
- Keys, synths and drum machines, often in stereo (two DIs or a stereo DI).
- Acoustic guitar with a built-in pickup.
- Laptop or playback, to send tracks cleanly into the console.
Put it straight in your rider
With RoboRider you build a clean input list, stage plot, technical and hospitality rider in one professional PDF. Free to try.
Start your rider →48V and ground lift
An active DI often needs 48V phantom power; note that in your input list. Most DIs also have a ground lift switch to remove hum from earth loops. Handy to know, but the crew usually handles that on site.
How many DIs, and where to note them?
Count your direct sources: bass, two channels of keys, an acoustic guitar and a laptop already make five DI channels. List them per channel in your input list with “DI” in the mic/DI column and an X for 48V where needed. In RoboRider you pick that straight from the dropdown.
Read next: How to make an input list → · Which mic for which instrument? →