This blog post is going to explain basic MIDI (Musical Instrument Digital Interface) connections. The way to think about MIDI is that the “out” is where you would send the note out from your device. So if you think of an electronic drum kit, MIDI out would send the notes that you're playing out to another unit. The other unit that you're connecting to would need to be receiving an input. So if you're connecting to a sound module, you would go from the “out” on the electronic drum kit to the “in” on the sound module. So as you play the drums, you would be able to hear the notes playing out on the sound module, and you could change the sounds in that sound module to suit those notes.

The other thing that you can have is a “MIDI through”, which is also a form of output. So say if you had multiple devices, you might have a sound module, a computer, and maybe an effects device. You could go from your “MIDI out” on the first device into the “MIDI in” on the second device. The “MIDI through” on the second device is a copy of that input. So you can then go from “MIDI through” on the second device to “MIDI in” on the third device.

A lot of guitar pedals these days also use MIDI. They may be chained up in a loop so that you can control different parameters while you're playing. For example, you might be synchronizing a time clock. So if you have a time clock with your pedals, they might be synchronized so that they're all in time when they're oscillating or delaying. You can also use MIDI to control things like the Joyo Cab Box, and you can use MIDI there to send a program-change command. So with that program change command, you could set up a multi-effects pedal and the Joyo Cab Box all to change at the same time.

Need more information? Check out this video: