Alan and David on F3/A4

[Ric Brekne]

Hi Bob

You are absolutely correct Bob. And this is exactly what I have written 
on three posts now. Alan and Ed... you may want to correct the line 
before posting it to the exams group :)

David Renaud put it yet another way and he was also quite correct. He 
simply stated that the inharmonicity in cents that A4(2) has for the 
given piano will be transfered to A3 when a perfect 2:1 octave type is 
tuned.  He left it up to the reader to figure out which direction that 
error was in. Course all that is based upon handling the A3 test in the 
same way as you would the A4 test. And THAT would be an error .... if 
your goal is as close to 440 as you can get that is.

Cheers
RicB


/Bob Davis writes:

A small correction. Recently I have read:

"Therefore, if you very accurately match the beat rates of F3-Fork and
 F3-A4, you will tune A4 sharp every single time!"

and
"If f3 a5 method is used with A5 as the coincident partial then A4 will be
sharp."

Not meaning to embarrass anyone, but just to avoid confusion to those
learning the trade, this is not correct. A perfectly tuned 440 A4 on the 
piano
produces a second partial which is slightly sharp of 880. IF the fork 
produces 880
at A5 (which has recently been called into question), we would have to 
bring A4
DOWN (under 440) to match its 2nd partial to the fork's 2nd partial.
/
Bob Davis

RicB wrote earlier:

/Using F3/A4 simply requires you to take into consideration that you are
dealing with a 5:2 coincident and, as several of you have pointed out,
because the pitch fork yields 880.00 Hz at this coincident  the
resulting fundemental for A4 will be just *_unde_r* 440Hz because of the
inharmonicity of pianostrings. This is however quite an easy matter to
compensate for... I would argue every bit as easy from a practical
standpoint as executing the routine above. In both cases you are simply
required to controll beat rates for the relevant comparisons appropriatly./