para-inharmonicity and tuning curves

Richard Moody remoody@easnet.net
Sun, 23 May 1999 01:53:56 -0500


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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