What MIDI Is and How to Create a MIDI File

Four words:

"Musical Instrument Digital Interface".

Generally, MIDI is a way that computers and musical devices "talk" to each other. Specifically, MIDI is a way that devices such as keyboards, DAW's of other computers (Digital Audio Workstations, or "music softwares" for you super beginners out there) transfer specific information about a recording, involving information about each note that's been recorded:

1. What key is each note;
2. Length of each note;
3. Placement of each note (where that note is in the recording);
4. If there's a chord, what are the notes of that chord, how long each note is in that chord, etc

So if I have a Keyboard, and I record a bunch of notes in that keyboard, and if I want to transfer all those notes from that keyboard into my computer using, say, Logic Pro. I would transfer it via MIDI format (I will show you how to transfer MIDI data in another blog).

So why is MIDI even necessary and how is this different than a regular audio recording? MIDI is mainly important because once you transfer that data from one device from another, you can use that second device to make changes or edit that MIDI file from it's original format in the first device; you can change the notes around, change how long or short those notes are, change the placements of those notes, and even change the instrument used to play the recording. So, say if you're not a fan of recording songs using a DAW and want to record a song by using the keyboard instead, but you can't stand the lousy instruments that came with that keyboard (and would prefer an instrument from your DAW), you can still record the song on that keyboard, then transfer that data into your DAW via MIDI, and then use one of the instruments in that DAW's library to replace that ugly instrument your keyboard used.

If you were to record that song via Audio recording, your DAW will record everything "merged" together as is. So not only won't you be able to change the notes around, but your DAW will also record that ugly instrument from your keyboard and you won't be able to change that either.

Let's take a .doc format (MIDI) and a PDF format (Audio recording) of a Microsoft Word document (Device), for example. If I create a document using Microsoft Word (Device #1) using one computer, save it as a ".doc" format (MIDI), then open that file from another computer using Word, or any other software that takes .doc files (Device #2), I can add words, take out words, change the font color, and pretty much anything else I could do with Device #1. However, if I took that original .doc file, saved it as a PDF (Audio recording), then tried to open it up using Word or Preview (mac software for opening JPGS, PDFs etc), I can't make those same changes because everything has been merged or "glued" together. That's pretty much the difference between a MIDI file and an Audio file.

This video shows you how to use one device to create a MIDI file (Logic Pro), and how flexible a MIDI file allows you to be in editing and changing your recording:

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