MIDI Thru; when to use a MIDI Thru Box

In response to last week’s tip on MIDI routing (see inSync 7/10/00) one astute reader pointed out a potentially troublesome detail that was left out. If you have a few MIDI instruments (as was the case with last week’s question) it is fine to daisy chain them together using MIDI Thru and MIDI IN connections. This, however, does produce a small delay as the signal is transferred through each device. Since this delay is cumulative, the timing of your MIDI system may suffer if you try to go through too many devices in a chain. If you fear this may be the case in your system there is an easy solution. You can get a hardware device known as a MIDI Thru Box. This is a (usually pretty inexpensive) device with one MIDI IN and several MIDI Thru ports. You attach your source to the IN port, and attach each module to a separate Thru port. Not only will this cut down on the cumulative MIDI delay, but it will keep the devices much more closely in sync with one another.