How to Connect a Direct Box DIby Greg Boone
A direct injection unit, commonly referred to as a DI, is used to convert a line level input, such as a musical instrument, into a microphone level input. This is useful, for example, when a mixing console has only microphone inputs available, but a line level instrument needs to be plugged directly into the console. The direct injection box converts the signal to match the available inputs.
Identify the instrument's output jack. This will likely be a hole somewhere on the instrument that accepts a connection from a 1/4-inch diameter instrument cable. The output jack is where the electronic audio signal will flow from the instrument.
Connect a 1/4-inch instrument cable into the instrument's output. The instrument cable should have two male ends. This cable is the vehicle that delivers the audio between the instrument and the DI.
Connect the other end of the 1/4-inch instrument cable into the DI box's input jack. This jack is sometimes labeled "in" or "input." Making this connection is essential to the proper functioning of a DI. This sends the audio signal into the box, where it will be processed and converted from line to microphone level.
Connect the female end of an XLR cable to the DI box's output jack. The output jack is usually on the opposite end of the input jack and often labeled "out" or "output." It is important to note that this output jack is an XLR connection, requiring a matching cable. Most microphones use this kind of cable. XLR cables have three pins on one end (the male end) and three holes on the other end (the female end).
Connect the male end of the XLR cable into an available microphone channel on the mixing console. The microphone channel is usually at the top or bottom of a channel and has three holes to receive the XLR. This connection sends the converted signal into the mixing console.