source file: mills2.txt Date: Sat, 18 Jan 1997 07:01:24 -0800 Subject: Commas, voice leading and pitch memory From: Gary Morrison <71670.2576@compuserve.com> > It looks > like in each case one tone makes a comma [is pseudo-comma the more > accurate term here?] shift, I'll address Steve's other thoughts shortly, but I just wanted to address this terminological question quickly. Although this tuning ... "discrepancy" I suppose it could be called ... arrives from the same sort of mechanism as a (syntonic) comma error in JI, Ivor Darreg, and probably others, referred to this it as a "pseudocomma" for two reasons: 1. The size of the discrepancy is much larger, especially in the case of 22TET (somewhat less so in the case of same effect in 34TET), than a 21.5c real syntonic comma. In 53TET, however, this is not the case at all. 2. A real comma scenario can give rise to an (theoretically) indefinitely large sequence of pitch changes. That is easiest to see in the wandering tonic case: If in the JI scenario you let the tonic drop by a syntonic comma and repeat that progression over and over each time dropping by 81:80, you'll never quite creep down to precisely any pitch within the original "source scale" (as Steve aptly called it). In the case of 22TET or 34TET on the other hand, you'll never create any pitches that are not already in within your original set of 22 or 34 pitch classes. I personally agree that these important-enough reasons to merit using the term "pseudocomma" instead of comma. Others may disagree or maybe not. Received: from ns.ezh.nl [137.174.112.59] by vbv40.ezh.nl with SMTP-OpenVMS via TCP/IP; Mon, 20 Jan 1997 21:38 +0100 Received: by ns.ezh.nl; (5.65v3.2/1.3/10May95) id AA09795; Mon, 20 Jan 1997 21:41:42 +0100 Received: from ella.mills.edu by ns (smtpxd); id XA09808 Received: from by ella.mills.edu via SMTP (940816.SGI.8.6.9/930416.SGI) for id MAA03150; Mon, 20 Jan 1997 12:41:39 -0800 Date: Mon, 20 Jan 1997 12:41:39 -0800 Message-Id: Errors-To: madole@mills.edu Reply-To: tuning@ella.mills.edu Originator: tuning@eartha.mills.edu Sender: tuning@ella.mills.edu