What is MIDI
MIDI (Musical Instruments Digital Interface) files are still little
understood, I think:
What it isn't: A MIDI file is not an audio file since it contains no
sound of its own.
What it is: It's a relatively small text file, its main
advantage over audio files, which tells your sound card or sound module
how and what to play: what patches (musical instruments, e.g. violins.)
to use, what notes, rhythms, note lengths, tempos, loudness,
reverberation etc. are desired. Sound files (Wav, AIFF, MP3s) may be
made from them and this will give a true picture of the sound source
the files were optimized for. My files are mostly done for the Roland
M-GS64 sound module, an early Sound Canvas model and should play
optimally on any Sound Canvas, providing that the software they are
imported into can accept system messages. Other sound sources may give
a more or less decent approximation of the sound I had in mind.
MIDI files cannot generally compare to live or recorded
performances of the same music but good ones can approximate them. Use
of electronic patches such as the warm pad or sound effects like the
bird (absolutely necessary in Respighi's Pines of Rome!) or other
patches add additional flexibility as do the combined Audio-MIDI files
which add additional audio tracks to the MIDI sounds but aren't really
compatible as a pure standard MIDI file (SMF) is.
About "sound fonts": These are largely for Windows setups
and others have often suggested I use them as a sound source even
though my setup (Mac OS) has, till recently, not been font-capable.
But I have recently been using Myriad's Harmony Assistant
with Virtual Singer and examples of this technology may be found in the
"singing scores" on my page. HA is indeed capable of using sound fonts
as an audio source, even in Macintosh, though I largely haven't found
them satisfactory so far. HA-VS is, in fact, not really pure MIDI which
cannot sing any words (unlike VS), but uses audio samples within the
files themselves.
On the whole, I do think this technology is very promising
(and the Myriad software quite inexpensive!).
Edward Gold
