source file: mills3.txt Date: Tue, 13 Jan 1998 02:57:04 +0100 Subject: Re: MIDI/Audio wish list From: mr88cet@texas.net (Gary Morrison) >Gary, would you mind very briefly outlining how the Ensoniq works for >ATS? Supposing you wanted to map the sampler for a '22-ET string >trio' (to use my previous example) - would it be easy? First of all, Ensoniq's "pitch tables" cover the full range of MIDI key#s, each independent of the others. Each key may have any arbitrary pitch you'd like it to, irrelevant of the pitches you assign to any of the other keys. (Well, each key's pitch is arbitrary within available pitch resolution of course.) Each instrument may have as many as 8 pitch tables (although selecting more than four rapidly is a bit tricky). To set up a repeating pattern of pitches, such as 12-Toned Ptolemaic JI in C, you enter the pitches for the keys C4 through C5. You would set, for example, E4 14 cents flat of the 12TET reference. (Actually, that's not exactly true; you specify pitches between 0 and 99 cents above whatever 12TET pitch reference lies directly below it, so you'd define the E4 key top play an Eb4 86 cents sharp.) Notice that you set the pitch of both of the C4 and of the C5, the C5 being an octave higher than the C4. You then tell it to "extrapolate" the pitch table from C4 to C5. That causes it to duplicate the pattern of pitches between C4 and B4 upon the pitch you chose for C5, and again on C6, C7, C3, C2, etc. In my 88CET tuning scheme, what looks visually on the keyboard to be an octave, instead spans a 7:4 (88CET's very-close approximation that is). So in 88CET I set C4 and C5 to be 7:4 apart, and when I extrapolate the table, I get something that repeats in 7:4s instead of octaves. Now, 22TET... You have a very basic question to answer before you can set it up. What keyboard mapping do you want? How do you want pitches in the tuning to map to keys on the keyboard? A common way is to map them "linearly", each key 1/22nd of an octave apart, mismatching octave boundaries in the tuning with those on the keyboard. If that's the way you want to map it, then set the pitches of the keys C4 through Bb5 to successive 22nds of an octave, and extrapolate your table from C4 to Bb5. Many of Ensoniq's "synthesizer" series, like their VFX (and unfortunately unlike their samplers), have an additional pitch-table function called "interpolate", which creates equal divisions. So, to tune 22TET on the VFX, you... 1. Tune Bb5 to an octave above C4. 2. Interpolate the tuning between C4 and Bb5. This sets the 22 pitches between those two keys to successive 22nds of an octave apart. 3. Extrapolate the tuning from C4 to Bb5. This duplicates the 22TET tuning that "interpolate" created between C4 and Bb5 across the whole MIDI range. An alternative to mapping keys linearly is to break the tuning into several 12-toned subsets that can be mapped on octave boundaries, and switch off between them using the patch-select keys. SMTPOriginator: tuning@eartha.mills.edu From: mr88cet@texas.net (Gary Morrison) Subject: Re: MIDI/Audio wish list PostedDate: 13-01-98 03:24:53 SendTo: CN=coul1358/OU=AT/O=EZH ReplyTo: tuning@eartha.mills.edu $MessageStorage: 0 $UpdatedBy: CN=notesrv2/OU=Server/O=EZH,CN=coul1358/OU=AT/O=EZH,CN=Manuel op de Coul/OU=AT/O=EZH RouteServers: CN=notesrv2/OU=Server/O=EZH,CN=notesrv1/OU=Server/O=EZH RouteTimes: 13-01-98 03:24:17-13-01-98 03:24:18,13-01-98 03:24:07-13-01-98 03:24:07 DeliveredDate: 13-01-98 03:24:07 Categories: $Revisions: Received: from ns.ezh.nl ([137.174.112.59]) by notesrv2.ezh.nl (Lotus SMTP MTA SMTP v4.6 (462.2 9-3-1997)) with SMTP id C125658B.000D34AA; Tue, 13 Jan 1998 03:24:43 +0100 Received: by ns.ezh.nl; (5.65v3.2/1.3/10May95) id AA23219; Tue, 13 Jan 1998 03:24:53 +0100 Date: Tue, 13 Jan 1998 03:24:53 +0100 Received: from ella.mills.edu by ns (smtpxd); id XA23293 Received: (qmail 23676 invoked from network); 12 Jan 1998 18:24:52 -0800 Received: from localhost (HELO ella.mills.edu) (127.0.0.1) by localhost with SMTP; 12 Jan 1998 18:24:52 -0800 Message-Id: Errors-To: madole@mills.edu Reply-To: tuning@eartha.mills.edu Originator: tuning@eartha.mills.edu Sender: tuning@eartha.mills.edu