[CAUT] SAT numbers

[Avery Todd]

Thanks, Fred. I appreciate your comments. I just went ahead and
tuned/checked/adjusted everything aurally. It was a 45" studio (Pearl
River). I've never had that problem with the grands. Only the verticals! And
the tuning pins were SOOOOOO tight!!!!!!

Avery


On 8/20/07, Fred Sturm <fssturm at unm.edu> wrote:
>
> Hi Avery, Yes, it was I. I generally defaulted to an 8 - 10 F number when
> it was higher as read (I now use RCT).
> I came to believe, based on things I had read and conversations I had had
> (which I'm afraid are hazy at this point) that Al Sanderson had made a
> change to the FAC calculations to give more stretch to the bass, in response
> to criticism by people using the SAT for concert tuning. And I came to the
> conclusion that it was a "patch" that didn't actually make any sense for
> pianos with an inharmonicity profile that happened to have a plain wire, low
> tension F3. (Note that the Hamilton 243 and the various flavors of Acrosonic
> are essentially the same scale, somewhat foreshortened. But the smaller
> Acrosonics happen to have wound strings for F3. Why should there be that
> much difference in their tuning?)
> In analyzing the numbers, I simply couldn't come up with a reason for the
> portion of the tuning produced by the F number (it affects the bottom 2 1/2
> octaves, and only to a certain extent). It would make some sense if, say, F3
> were taken as the 6th partial of A#0 (extrapolate the 1st partial of F3, and
> use it to create a curve as the next to lowest of the 6th partials tuned).
> But it sure didn't seem to work that way. So I just started doing the
> default thing, and found that the curve produced worked quite well most of
> the time (I had found that with those larger numbers, I was constantly
> needing to intervene and narrow the octaves).
> I also always tuned the bass downwards (never started at A0) so that I
> would know what was happening and be able to intervene. The simplest way of
> "keeping and eye on things" was to play the notes a 5th and an octave above
> the note to be tuned (from time to time, no necessarily every single one),
> which would tell you how wide or narrow the 6:3 octave and the 6:4 5th would
> be (before tuning the note itself - meaning its 6th partial). If the 6:3 was
> going to be significantly wide (lights rotating sharp more than a bit), I'd
> change the setting until, as I recall, the octave above made the lights
> rotate just sharp, while the 5th made them rotate just flat. And then, of
> course, the ear decided if the note was "right" once tuned (keeping in mind
> that "right" is a vague notion on many of these beasts, with lots of
> conflicting reasons to go one direction or the other).
>  Regards,
> Fred Sturm
> University of New Mexico
> fssturm at unm.edu
>
>
>
>
>  On Aug 17, 2007, at 7:41 PM, Avery Todd wrote:
>
>  List,
>
> I have a question about high numbers on F on an SAT III. I tuned two Pearl
> River UP 115's today (studio size) and one of them had an F number of 15.1and the other had
> 14.9. I was getting way too much stretch as I went into the bass so I just
> ended up tuning them aurally!
>
> I seem to remember that someone (Fred Sturm?) mentioned some time back
> that he never uses a number higher than ?????. Am I correct? Or was it
> someone else? Just wondering what others of you SAT users do in a case like
> this. BTW, this is a VERY good reason why it's good to also be able to tune
> aurally!!!!!!! :-)
>
> Avery Todd
>
>
>
>
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