Getting it right ... was Octave Tuning

Matthew Todd pianotech88@yahoo.com
Thu, 23 Sep 2004 07:28:23 -0700 (PDT)


---------------------- multipart/alternative attachment
Thank you guys so much for the valuable insights you have given me.  They are my daily devotions!  I'll be printing them out and filing them.  Thanks again!
 
Matthew

Alan <tune4u@earthlink.net> wrote:
Tune it so the 10th (F3-A4) beats just noticeably faster than the F3-A3 third. If I am aural tuning I tune to personally tune with fast beating intervals (see Potter, Coleman, etc.) BUT it is very handy to be able to tune and recognize good 5ths and 4ths in your temperament to use as checks--including a check of your temperament octave, which is usually 4:2 or close to it. Tune the A3-E4 and D4-A4 5ths then listen to the fourths on E4 and D4, that will tell you immediately if your octave is good. Also, if you tune A4 then A3, then F3 (about 7 bps "Min-i-tonk-a, Min-i-tonk-a, Min-i-tonk-a, ...." ), then the F3-F4 octave (you with me?) then see if you can tune C#4 so that the beat rate progression of F3-A3, A3-C#4, C#4-F4, F4-A4 is smooth and even, then you can be certain you have a temperament 10th (F3-A4) that will work -- and 5 "anchor" notes to test your intervals against as you tune.
 
Another way is to use ghost tones. If you have a pretty quiet tuning environment, this will give you dead-on accurate 4:2s, 6:3s, etc. Of course, whether or not you WANT precise intervals is a matter of taste AND what the piano is trying to tell you.
 
If you're interested, here's a longish post on ghost tuning that I put up a couple of years ago.
 
https://www.moypiano.com/ptg/pianotech.php/2002-September/118743.html
 
(Just looked at that, and the archive formatting is kinda confusing. I'll attach the orginal Word  document to this post. It's good stuff to know about ...)
 
Have fun, you'll get it ... then you'll wonder why you ever had a problem with it!
 
Alan R. Barnard
Salem, MO

-----Original Message-----
From: Matthew Todd [mailto:pianotech88@yahoo.com] 
Sent: Wednesday, September 22, 2004 11:54 AM
To: Pianotech
Subject: Re: Octave Tuning


Now, how exactly do you tune the fourth partial of the lower octave note to the second partial of the upper octave note?  I have heard that some techs just tune the octave 1/2 a beat wide, and leave it at that.
 
Now you can call me stupid
 
Matthew

Don <pianotuna@accesscomm.ca> wrote:
Hi Mathew,

Current thought is that a unison is the only "pure" item in tuning. An
Octave can only be "beat free" at one partial at a time. Do an archive
search for octaves and you will get loads of hits.

narrowest possible octave 2:1; a3 to a4 beatless at a4
wider 4:2; a3 to a4 beatless at a5
wider 6:3; a3 to a4 beatless at e6

It is common to tune a3 to a4 somewhere between 4:2 and 6:3--just to make
the task a little more difficult. I believe this is what Virgil Smith does
when he attempts to tune the "whole sound" of the octave. I.E. his 4:2
beats at a rate which may "cancel" the beat of the 6:3. How long such a
"balance" will last is dependant on nothing in the enviroment changing,
including barometric pressure.

More on unisons:

We also have to deal with the "coupled" motion of piano strings. The bridge
is a f! lexible termination. Some studies have suggested that a one hertz
difference in two strings will result in zero beating heard. One hertz at
A4 is approximately 4 cents--a huge number for a unison to be "out". There
is also some suggestion that a truely "pure" unison gives the piano a
rather "dead" sound with poor sustain.

Inharmonicity:

There is no doubt that the impedance mismatch between the strings, bridge
and soundboard produces a measureable effect on the width of octaves. In
some cases this "para inharmoncity" can be a negative number.
Translation--the narrowest octave would be smaller than a "theorectical" 2:1.

Setting Temperament:

I'd suggest you use one of the "self correcting" temperments such as the
Baldassin-Sanderson. Have a look here:

http://www.accu-tuner.com/SATIIImanual/apf.html 

At 07:42 PM 21/09/2004 -0700, you wrote:
> need some help from all of you. Is it true that the two things that
&g! t;remain pure in a piano when we tune is unisons and octaves? And if we do
>that, the octave will have a slight beat to it, right? I think I missed
>something. You guys are great! Thanks!!
>Matthew 
>__________________________________________________
>Do You Yahoo!?
>Tired of spam? Yahoo! Mail has the best spam protection around 
>http://mail.yahoo.com 

Regards,
Don Rose, B.Mus., A.M.U.S., A.MUS., R.P.T.

mailto:pianotuna@accesscomm.ca http://us.geocities.com/drpt1948/

3004 Grant Rd.
REGINA, SK
S4S 5G7
306-352-3620 or 1-888-29t-uner
_______________________________________________
pianotech list info: https://www.moypiano.com/resources/#archives


---------------------------------
Do you Yahoo!?
vote.yahoo.com - Register online to vote today!

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.760 / Virus Database: 509 - Release Date: 09/10/2004





> ATTACHMENT part 2 application/msword name=GHOST TONES IN PIANO TUNING.doc
_______________________________________________
pianotech list info: https://www.moypiano.com/resources/#archives

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 
---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/53/e6/6c/58/attachment.htm

---------------------- multipart/alternative attachment--

This PTG archive page provided courtesy of Moy Piano Service, LLC