pitch

[Sambell, Ted]

Hello Denis!

Having read your post today (very valuable information) I am motivated to
get in touch with you; it is long overdue that I should do so, especially as
it is my last day here  at the Banff Centre, though I am coming back on an
ad hoc basis. In fact, April is already filled up wth other work
including a wierd commission to design and build a damper mechanism for a
santur (Iranian dulcimer) for one of the musicians here. 
I have just installed a set of hammers in a Yamaha C7, one of the older ones
with a 23 note bass, and used your spreadsheet program for the boring
angles. It worked perfectly for me, except that the angles on this piano
change from note 88 individually all the way down to the tenor break. I used
the tenor page for the treble angles and put them on a separate sheet. You
might consider an extra page for the treble (section(s)), or extend the
angles for all the sections other than the bass.I finally made a new brass
disc for the boring jig too, and fine adjusted the jig so that it bores on
axis. It works superbly at last, and is a real joy to use. I am thinking of
writing for the journal on hammers, and wonder if I could persuade you to
collaborate for a joint effort, especially on the calculating of the angles.

Last weekend I went to the PNW Conference; instructed two classes twice and
had a great time. Many of your old friends asked after you, so you are not
forgotten.

I trust you, Estelle and the children are all well and hope to hear from
you,

Fondest regards, Ted-----Original Message-----
From: Denis Brassard [mailto:brassadp@potsdam.edu]
Sent: Friday, March 30, 2001 9:14 AM
To: caut@ptg.org
Subject: Re: pitch


Greg,
If you are familiar with logarithms, there is a simple formula you can use
that works for every frequencies on any given note at the piano.
Here it is:

1+ Log (Freq./27.5)/ Log (2) X 12 = Note Number

In your post you mentioned 435 Hz.

1+ Log (435/27.5)/ Log (2) X 12  = 48.8021

48 is your note number, i.e. G#4 and the decimal part X 100 is the amount
that note is sharp; i.e. 80.21 cents.
A semitone being 100 cents, G#4 +80.21cts = A4 -19.79cts.
When you stated A 435 being offset by 19.79 cents, you were right on the
money.

Regards,

Denis Brassard,
Head Piano Technician
SUNY Potsdam
Potsdam, New York.


>Hi Greg,
>
>Each beat per second is roughly equal to 4 cents. Hence, 440 bps -
>435 bps = 5 bps X 4 cents = 20 cents. Your offset was pretty close,
>I'd say.
>
>Best wishes,
>
>Tom
>
>>Greetings folks,
>>    I recently tried to tune an older instrument that seemed as though
>>it was designed for 435. I went about it in an unusual way. Since I'm
>>just dense enough not to remember the formula I had to figure out how to
>>offset the ETD to read for 435. In TuneLab (check out the new TuneLab
>>PRO) I used the mouse on the left side of the floating boxes window
>>until the frequency said 435. When I did that the offset read -19.79.
>>Does this sound correct to you folks or did I mess up again?
>>    o.k. that's one more item off of my to do
>>list............................
>>
>>--
>>Greg Newell
>>Greg's Piano Forté
>>12970 Harlon Ave.
>>Lakewood, Ohio 44107
>>216-226-3791
>>mailto:gnewell@ameritech.net
>
>
>Tom Seay
>Piano Tech Office
>School of Music
>The University of Texas at Austin
>(512) 232-2072
>mailto:t.seay@mail.utexas.edu