Hi again richard: The fundamental was not tuned to 0.0 cents when I read it. These deviations are deviations from 0.0 cents at each equal temperament note location where the partials are. To get the amount of inharmonicity of each partial, you would have to subtract 2.1 cents from each to get the picture in relation to 0.0 cents deviations. In regard to your comment about flat partials, it IS possible to to have flat partials due to many perhaps unknown-as-yet reasons. The negative numbers of the odd numbered partials below however are due to the fact that the numbers were read at note locations which on the SAT are normally read as equal tempered relationships. The 3rd partial is read from a note location in equal temperament which is sharper than would be the 3rd partial. This machine reading notes normally makes the 5th interval narrow according to the requirements of equal temperament, but the 3rd partial of a string is not tempered, so it always shows sharper (by at least 1.95 cents) when measured by an equal tempered machine. Likewise when measuring a 5th partial with a machine which is built upon the principle of measuring tempered intervals (which are normally 13.687 cents wider than pure), the 5th partial will appear to be flat of the reference note by at least 13.687 cents. Jim Coleman, Sr. On Sun, 23 May 1999, Richard Moody wrote: > Hi Jim > I wanted to ask you but held off, thinking it would come up. You > mentioned.... > > > > the cents deviations of actual octavely related partials taken from > > my Steinway L, note C4. > > > > 1st partial 2nd partial 4th partial 8th partial > > > > 2.1 2.8 6.2 20.2 in Cents > > > > If I read it right does it say the first partial has a "cents deviation" > of 2.1 ? > > I can't figure out how the fundamental (commonly called the first partial) > can deviate by more than 0.0 cents let alone 2.1. > > Regarding the 20.2 cents for the 8th partial, I assume that is twenty > cents sharp. Does that mean the freq measured for the 8th partial of C4 is > 20.2 cents sharp from theoretical. (8 times the fundamental F*8 ) ? > > I know you know I need this like a (another) hole in the head, but why > does the SAT need to odd partials compared to ET?. Because of this > comparison is that why some of the readings have negative cents which > could be interpreted in real terms as a partial that is flat which is > acoustically impossible? > > Ric Wondering > > > > In anticipation of your next question, when you plot for, 3rd, 5th, > > 6th, and 7th partials, you must make a correction for equal temperament > > being the source of the readings. Here are the readings taken with > > and electronic tuning machine: > > > > 3rd partial 5th partial 6th partial 7th partial > > > > 5.9 -4.6 13.6 -15.4 > > > >
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