ABOUT MIDI MUSIC
You may be wondering just what MIDI music is and why it cannot truly be “converted” to another type of file like WAV or MP3 files.
The reason is simple, MIDI files are not sound files, while the others are. This is to say that other file types are actually recorded sound that is stored in a compresses format to make the files smaller, or sometimes, like on a CD, not compressed, and are simply recorded sound, like a tape on a tape recorder. The point is that non-Midi files contain recorded sound.
MIDI files are not sound files at all. A MIDI file is a set of instructions, similar to sheet music used by musicians. There is a part for each instrument that is to play with the default being piano because it is the easiest to do and because the MIDI file is normally generated with the musician sitting at an electric piano keyboard and this musician keys in each note, or cord, by hand. What is recorded is the perimeters of each note, pitch, length, loudness, and so on. Anyhow the MIDI file is really just the description of the music that is to be played. The intended use of a MIDI file is to be fed back into the electric piano, and the piano reproduces (plays) the music. It is similar in function to the old player pianos that have paper rolls, using rolls of paper with holes punched in the paper. The roll is not music, it is a set of instructions that the piano reads, then the piano makes the music.
The problem with a computer playing MIDI music files is that the computer program must have the equivalent of an electric piano built in. This is what you hear, not a recording of the sound, but the sound your computer creates based on instructions from the file. This being the case means that the sound you hear may sound different depending on the program on the computer, or other device that reads MIDI music and creates the sound.
Another point is that MIDI music has a number of different tracks and they do not always agree with the reader, so a percussion channel can sometimes play as a music note instead of drums and the result is not pleasant listening.
Most computer sound programs do not include the MIDI capability but some will have a ‘plug-in’ that will add the capability. If you have an electric piano that will play MIDI files, you should be able to play it on the piano assuming you can get the files to the piano.