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<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue =
2px solid"><FONT face=Arial size=2>"I strike the F below the A and liste=
n to the fork A along with the F. I count those beats. Then I remove the for=
k and play the F and the A and count those beats. "</FONT></BLOCKQUOTE></DIV=
>
<DIV>I don't know if the writer really meant literally "the F below the A", =
but I also saw a reference in another post to a "F2-A3" comparison with the =
fork, so I just wanted to make it clear that although F2, F3, and F4 wi=
ll all beat against A4, only the F2 [2 8ves + M3rd] will give an accura=
te comparison between an A4 fork and the A4 note on the piano. Here's why:</=
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<DIV> </DIV>
<DIV>The 5th partial of F2 is approximately equal to the fundamental of A4. =
In a tuned piano, it will be about 4 beats flat of both the fork and the not=
e, but it can be set anywhere comfortable. I like 5 or 6 beats even better. =
When A4 on the piano is in tune with an A4 fork, the bea=
t of either against the F2 beat-producer note will be the same. This is=
such a great method because, even as the notes become in tune, the bea=
ts remain in a comfortable range [4 to 6/sec] in which the ear is amazingly =
adept at comparison. On the other hand, in trying to match a note directly t=
o a fork, the closer the match, the slower the beat. And, it never becomes c=
ompletely clean, because of beating between harmonics of the source and "inh=
armonics" of the piano. Just last Saturday, our Chapter set an A a=
s a group by the F2-A4 method, and were very quickly able to agree on a=
setting which we then measured electronically as being only 0.2 cents off. =
That's not bad. By the way, we used an AccuFork. We had a grand wi=
th a sostenuto, which you can use to hold down the F2, but I =
also demonstrated playing it and jamming a mute between it and F# to ho=
ld it down, then tuning the A4.</DIV>
<DIV> </DIV>
<DIV>The 5th partial of ~F3~ on the other hand, is ~A5~, which matches the d=
esired A4 at its SECOND partial, A5 [a 5:2 match]. The A5 produced=
by the fork is harmonic, but that produced by the piano is a little sharp. =
Matching this coincidence causes the piano's A4 to be slightly flat. F4-A4 [=
a 5:4 match, coincident at A6] would produce an even flatter A4, with equal =
beats between the fork and piano.</DIV>
<DIV> </DIV>
<DIV>I hope that's clear. We're probably all on the same page, but I just wa=
nted to make sure everyone out there knows why only F2 works accurately.</DI=
V>
<DIV> </DIV>
<DIV>Bob Davis</DIV></BODY></HTML>