source file: m1513.txt Date: Mon, 24 Aug 1998 02:18:10 -0700 (PDT) Subject: Re: Promenade tuning examples From: Mark Nowitzky Hi David; thanks for your email! At 03:03 PM 8/20/98 EDT, you wrote: >About a year ago I listened to these Moussorgsky examples and picked the >12-tET one. Since then, I've learned that SoundBlasters respond to MIDI >pitchbend commands in unconventional ways. This means that I was hearing the >ET one correctly, but the JI version was out of tune. No wonder it sucked! When I pieced together the Moussorgsky MIDI files, along with other MIDI files reachable via http://www.pacificnet.net/~nowitzky/justint, I also found out that "pitch bend" did not seem to have a standardized implementation. At the time, I was hoping I found the most-commonly-used implementation. It seemed to be most often implemented as follows (where 100 cents = an equal tempered semitone): bend -8192 means "bend flat 200 cents bend -4096 means "bend flat 100 cents bend +0 means "don't bend it" bend +4096 means "bend sharp 100 cents bend +8192 means "bend sharp 200 cents In other words, I hoped it was 4096 per half-step, and that it was "linear". I haven't experimented with different sound cards too much, but so far I found out that some will completely ignore pitch bend commands, and others will bend the notes to some amount other than a half-step for a value of 4096. I even heard that the amount it bends for value 4096 can be some sort of user-changeable parameter, which might be okay for some sort of live performance machine with a real pitch wheel on it, but would give all sorts of weird sounds when trying to playback a MIDI file on a different PC. >Having now heard it on a Mac, which does respond to PBs in the standard way, I >must certainly retract my previous vote and cast it in favor of the 5-lim JI >version. I'm still rooting for 5-limit JI myself! I was considering having some sort of "test your sound-card" web page, to see if the user's sound card reacted the way it needed to get the desired tuning. I stumbled across someone else's page that had some microtonal examples, that didn't work on my PC. Instead of using "pitch bend" commands, it was using some sort of "system exclusive" commands, which I guess only worked on a particular manufacturer's sound card (It might have been for a Roland keyboard in this case). Anyway, that page did have a "testing" option, which helped me see that I didn't have the right equipment. It kept playing a note, saying that the note should be changing (and it didn't change on my lousy sound card). >Thanks for a fun and informative page! Thank you for the fun and informative email! --Mark +------------------------------------------------------+ | Mark Nowitzky | | email: nowitzky@alum.mit.edu AIM: Nowitzky | | www: http://www.pacificnet.net/~nowitzky | | "If you haven't visited Mark Nowitzky's home | | page recently, you haven't missed much..." | +------------------------------------------------------+