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./
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