Studio or Stage, A DI Box Is Your Friend

“What does a DI do?” and “how can a DI benefit me?” are two of the many pro-audio related questions we field at Alamo Music Center with regularity. Professional musicians and audio engineers usually have a number of these in their audio arsenals, and many will have strong feelings on the DIs that they employ. Oh, and before we go any further, DI is shorthand for “direct inject”, just in case you were wondering.

DIs are used extensively in the studio by recording engineers, and every decent music venue will have a stack on hand as well. With home studios continuing their upward trend, many aspiring hit-makers will find that a good DI or two is a necessity, especially when recording keys and unadulterated guitar and bass tracks that could be used for re-amping purposes later. Re-amping is the process of taking pre-recorded material and patching that signal back into an amplifier for further manipulation.

Radial Pro 48 Active DI Box (CLICK FO DETAILS)

The two main flavors of DI are passive and active. The primary function of a DI is to match the impedance of an unbalanced instrument cable (hi-z) to that of a balanced microphone cable and preamplifier input (low-z). Active DIs can also be used to boost the signal of instruments that may have a lower than usual output or with long cable runs where the audio signal can weaken. Most active DIs utilize phantom power (48 volts) that’s generated by the mic pre and some also take a 9 volt battery if phantom power is not readily available. Passive DIs are not powered and will work with greater efficacy with instruments that have a high output.

Radial Pro DI Passive DI Box (CLICK FOR DETAILS)

Not all DIs are created equally, yet they all serve the same purpose. Some DIs are in stereo, which is perfect for stereo keyboards, samplers, drum machines, and other instruments that incorporate stereo signals into their architecture. Other features that one might find on a DI are: ground lift, through jack (plug into an amp and preamp!), pad switch for signals that are too hot, and possibly a phase switch for irregularities in wiring which can lead to phase cancelation (pin 2 hot/pin 3 hot).

As you can probably tell, DIs are available in different configurations, serve multiple purposes and are a vital part of the signal chain wherever music is being made.  A good DI is going to insure that the signal from your instrument is going to enter a microphone preamplifier with as little degradation as possible and give you the signal you so rightly deserve.  Be sure to add a DI to your recording and/or performing rig soon!