Why can't i access /dev/dsp or /dev/snd on my XO

Mikus Grinbergs mikus at bga.com
Mon Jan 21 23:52:23 EST 2008


> By the way -- as far as microtonal and xentonal and "world music scales"
> are concerned, MIDI's pitch bends are an awkward hack. Serious
> *microtonal* algocompsynth practitioners either have to spend time
> working around MIDI or use something else.

I'm just a dilettante, not a musician.  But once upon a time MIDI 
specifications formed my spare-time reading.  The problem with using 
MIDI to express music is that the fundamental MIDI "atoms" are 
'notes' (each representing a frequency).  Thus in MIDI the sounds 
that occur need to be expressed as a series of 'notes'.  This 
corresponds well with certain "Western" music that uses uniform 
"proportional frequency scales" (e.g, octaves) subdivided into 
'notes' (e.g., the 12-tone system).  If a sound does not fit the 
MIDI-assigned frequency of the nearest 'note', 'pitch bend' can be 
used to adjust that instance of the 'note' to the frequency desired.

What I seem to recall was that the MIDI "tuning standard" (in 
conjunction with the "instrument" definition supplied to the 
MIDI-player) permitted the definition of a specific 'note-number' as 
__the__ "pivot frequency", with higher-numbered and lower-numbered 
'note-numbers' being defined explicitly at proportional frequencies 
lower and higher than the "pivot frequency".  As long as the 100+ 
possible 'note-numbers' (plus 'pitch bend') were enough to cover the 
frequency range of the musical composition, this MIDI notation would 
suffice to *express* that musical composition (even for "world music 
scales").  [Of course, if the __MIDI-player__ did not support this 
"pivot frequency" mechanism, the wrong sounds would be produced.] 
[Also, there is an __Organ__ project which uses SYSEX messages to 
define "custom" sounds, then uses MIDI-events to play them.]

mikus




More information about the Devel mailing list