source file: mills2.txt Date: Tue, 11 Jun 1996 12:02:48 -0700 Subject: Post from McLaren From: John Chalmers From: mclaren Subject: construction of a 19-tone m'bira -- The Sonic Arts Gallery is constantly boiling with new ideas and plans for new instruments, so it came as no surprise when Jonathan Glasier began work on a 19-tone m'bira. Patterend after Bill Wesley's "array m'bira," this instrument is to an african thumb piano as a 747 is to the Wright brothers' biplane. Bill Wesley's "array" arrangement of tines places consonant intervals closest to one another, while putting dissonant intervals far apart. Thus if you stroke the tines of one of Bill's m'biras at random, you get a set of fifths, rather than a jangle of semitones. This has had some interesting effects when translating the "array" into 19 tones to the octave. Originally designed by Pythaogrean intonation, the 2-D "array" of crisscrossing 5th and 4ths seems to accomodate well the 19-tone system. No doubt this is because 19 boasts fine fifths, only 7 cents flat of the just 3/2. The array would probably also work as a keyboard arrangement for 17, 22, 27, 29, 31, and most of the other equal temperaments with good fifths. The real surprise, though, is how close this microtonal acoustic instrument sounds to its 12-TET cousin. The 19-tone equal tempered scale truly is the first step outside 12. --mclaren Received: from eartha.mills.edu [144.91.3.20] by vbv40.ezh.nl with SMTP-OpenVMS via TCP/IP; Tue, 11 Jun 1996 21:06 +0100 Received: from by eartha.mills.edu via SMTP (940816.SGI.8.6.9/930416.SGI) for id MAA04775; Tue, 11 Jun 1996 12:05:59 -0700 Date: Tue, 11 Jun 1996 12:05:59 -0700 Message-Id: Errors-To: madole@ella.mills.edu Reply-To: tuning@eartha.mills.edu Originator: tuning@eartha.mills.edu Sender: tuning@eartha.mills.edu