If you are new to Midi, reading this can be a very good start:
Midi is the standard exchange format of computers and music devices such as: synthesizers, drummachines, guitars, basses and many other musical instruments.
Midi stands for Musical Instrument Digital Interface.
Basically, the software encodes this string of musical events and stores them for synchronized playback in much the same way as word processing interprets keystrokes on an alpha-numeric keyboard, stores them, and then reproduces the finished result on a printed page. In this sense, the midi file consists of musical "letters" which are strung together to become the song, much like the alpha-numeric keystrokes become words, sentences, paragraphs, and eventually an entire essay.
The sequencer (a computer software) stores music as a string of time-specific events. These include the selected sound (an instrument from the sound card), the time at which it is sounded (relative to an at-zero starting time), its velocity (the strength of the initial impact), its note value (the pitch), duration (length), and any manipulation (pitch bend, vibrato, chorus, etc) that occurs during its sounding.
This protocole (a kind of language) has become the standard allowing computers, synthesizers, digital recorders, effects modules, and many other digital musical devices to communicate with each other.
Midifiles are quite small. A file that would cost in Wave format (*.wav) 6 MegaByte (6 MB) costs in Midi format (*.mid) only 10-100 KiloByte (0,01-0,1 MB).
Midifiles are small and easy to make. -Midi is an international standard. On most computers is software available to play midifiles. It is a marvelous tool for the composing, arranging, and playback of musical scores and enables the musician to write, review, refine, and eventually record his or her music. It has made the music-creating process much faster and simpler. No longer must one sit at the piano with music paper, pencil, and eraser, and then hope for the best at a rehearsal or performance. The music is always readily available for instant editing, revision, and enjoyment.
What are the drawbacks of MIDI?
You can only produce synthesizer sounds. You can produce lots of different instruments (depending on your music device), but no other sounds than that. N.B. With that, you can do more than you can imagine!
How does it helps a composer-arranger?
As a composer-arranger, no longer do you have to assemble a band, find a place to play, deal with other musicians and their no-shows, personal problems, or shortcomings, or hassle with neighbors whose musical tastes may differ from yours (use headphones!). The benefits far outweigh the cost, and the results are most rewarding!
Is Midi an International Standard?
Yes, in fact the general midi files are called standard midi file (smf), but besides this kind of file there are other standards as GS and XG midi files.
What do I need to make my own MIDI-files?
There are some good programs, like Cubase, Cakewalk Pro and Voyetra Midi Orchestrator Plus to help you make your own midifiles. With those programs you can even create midifiles without having an instrument connected to your computer!
How do I connect my computer to a Midi device?
Connecting instruments to your computer is easy (at least for synthesizers). You have to buy a midi cable, which you can get at any computer store. Then connect the cable to the soundcard (in a kind of joystick connector probably at the back of your computer) and to the instrument. The connections should go Midi In->Midi Out and Midi Out<-Midi In...When the connection is made startup a midi program, set your preferences in that program (there almost always is in those programs a menu where you can set input and output devices) and you've got your homestudio to work! In case of problems, check always the manuals and help files, the homepages for the software developpers and the newsgroups for the respective programs.
The original MIDI specification was developed in the late 70x as a means for electronic keyboard players to play two or more keyboard instruments from just one keyboard. That way, someone like Keith Emerson could "layer" his MOOG synthesizer from his Yamaha DX7 keyboard and have the two sounds going simultaneously to create a richer, beefier sound. Within a short period of time, dedicated hardware "Sequencers" were being developed. These "Sequencers" were like digital tape recorders, and allowed musicians to play a song on a keyboard and the MIDI output port would send the data directly to the sequencer to record the song. The musician would then press the "Play" button (just like a tape recorder) and the music would play back the performance exactly like the original. Beside that, it was being played "live" (by the sequencer), so sound quality reduction was no longer a problem as with traditional tape recorders. About the same time, the Apple Macintosh and IBM PC were also evolving rapidly. Software developers came up with sequencing software for these computers. The software offered much greater capabilities than their hardware counterparts. Several years later, "Soundcards" became a standard on personal computers. Soundcards typically employ two methods of sound generation. The main source are PCM type recordings (*.WAV files on PC's). These are actually digital recordings, like the ones your CD player reads when playing a Compact Disk on your stereo system. While impressive to hear, these files use about 10 Megabytes/minute to produce stereo sound. These can use up quite a bit of hard drive real estate, in a very short period of time. The second method a soundcard uses to produce sound is on a built in synthesizer. Music is played when a MIDI file triggers the sounds on the synthesizer. These MIDI files are small, and require very little storage space (a few kilobytes vs. a CD's 30 megabytes for a 3-minute song). As you can see, CD music files requires THOUSANDS of times more disc space for the same song. While little space is required for the same song, most lower end soundcards employ a cheesy-sounding FM synthesizer. We've all heard those FM synthesizers when hearing tunes on those electronic holiday cards or when we are put on hold at some places. They sound kinda like cheap electronic bells.
What is "Wavetable" synthesis?
Higher end soundcards (such as SoundBlaster AWE, Ensoniq Soundscape or Roland RAP-10) employ a different method of synthesis called "Wavetable" synthesis.
The sound quality of most wavetable soundcards is significantly better than the FM-based cards.
Wavetable synthesizers use actual "digital samples" of real musical instruments, to generate music. These are real, hi-fidelity recordings of the actual instruments. When a MIDI file is played through a high quality "Wavetable" soundcard, the sound quality approaches that of an actual CD, but without the storage requirements. (Remember, MIDI files take a fraction of the space required by WAV files.)
General MIDI (referred to as GM from here on out) was developed in the past 5 years and is the basis for "Wavetable" synthesis. GM is actually a set of 120 standard sounds, plus drum kit definitions. All "Wavetable" synthesizers and soundcards use the GM soundset to assure compatibility between the manufacturers.
Midi Glossary
( Worth of being checked out)
Midi Glossary