source file: mills2.txt Date: Tue, 27 Aug 1996 22:26:30 -0700 Subject: 7:4 versus... From: HFORTUIN@delphi.com On Aug. 26 Kami Rousseau asked: >>What is your opinion on sevenths? What is the difference between 16/9 and 9/5? (I you tell me that the difference is a comma, I will have to kill you. What I want to know is when to use the two different intervals.) I haven't dealt with 16/9, but I'm a great believer in 7/4, 7/5, 7/6, and their consonant, or at least relatively consonant, nature. I really enjoy contrasting the 9/5 and 7/4 in seventh chords (tetrads) built on the same root. In 12-ET, these two intervals are represented by the 10th chromatic pitch, and our ears bend the pitch to best fit the harmonic context. As proof of my previous sentence, and to silence any sceptics about the importance of 7/4: --create a pure 4:5:6:7 chord on your synth --create a 4:5:6 triad, but add a 9/5 on top (9/5 * 4/4) --create a 10:12:15:18 chord on the same root as each of the previous chords After you are convinced thatchord #1 is smoother than chord #2, play chord #1 and #3 one after another, and enjoy the perfectly consonant harmonies with their thoroughly microtonal soprano line. In ET contexts, 22 provides a good 7/4 (better than 19), and 27 and 31 are each progressively better yet. Another ear-shock: 22 also has a very good 11/8. Try playing a 4:5:6:7:9:11 chord in 22, and you'll see what I mean. We all know that in 12, we must omit the major third of this chord (5/4), but notice how smooth this chord is with good 7/4 and 11/8 approximations! --Harold Received: from ns.ezh.nl [137.174.112.59] by vbv40.ezh.nl with SMTP-OpenVMS via TCP/IP; Wed, 28 Aug 1996 17:25 +0200 Received: by ns.ezh.nl; (5.65v3.2/1.3/10May95) id AA03239; Wed, 28 Aug 1996 17:27:05 +0200 Received: from eartha.mills.edu by ns (smtpxd); id XA03254 Received: from by eartha.mills.edu via SMTP (940816.SGI.8.6.9/930416.SGI) for id IAA00419; Wed, 28 Aug 1996 08:27:02 -0700 Date: Wed, 28 Aug 1996 08:27:02 -0700 Message-Id: <199608281525.IAA00324@eartha.mills.edu> Errors-To: madole@ella.mills.edu Reply-To: tuning@eartha.mills.edu Originator: tuning@eartha.mills.edu Sender: tuning@eartha.mills.edu