What actually is MIDI and how does it function in a system?

Question

Sorry for the primitive question but this is a topic where I'm completely blank and has been a mystery for me until now. I had some readings on the net but couldn't get a clear picture. All say MIDI is an interface.

I thought about it and maybe a short brief journey of MIDI music from a MIDI file in a PC to the computer speaker would help to see the bigger picture.

I have some midi files aka music files in MIDI format and when played by a media player you can hear the synthesized music. Here as an example can be downloaded and listened to an example "Confutatis" from Mozart's Requiem.

So what happens right after the program runs in terms of the information transfer?

Here is what I guess:

The program code(midi file) executes ---> The CPU and RAM sends the digital data in the program code to the sound card via a MIDI interface ---> The soundcard probably knows the MIDI coding converts the digital data to analogue audio----> This audio is amplified and sent to the speaker. ???

The above might be completely wrong and I cannot find a flow chart or any circuitry about it on the net. An example with an electronic keyboard and MIDI also would be fine.

Answer 1

Midi is an interface standard, a physical communication interface and protocol standard.

It was designed to let electronic instruments and synthesizers communicate with each other to allow performers to produce live music.

Midi controllers send notes to midi synthesizers for them to generate sounds.

Its basic representation is in terms of channels/instruments/controllers, notes, and timings. That allows midi files (controller commands) to be rather small.

Although it is possible, I really doubt the sound card understands midi at all. Instead it is more likely that a software synthesizer generates the requested sounds.