Octave Tuning

[jason kanter]

There are 6 tests for a perfect 12th. (see Jorgensen, Big Red, page 756)

Let's assume we are tuning F3 to C5.

1. The fifth-octave test. Mistune C4 so that there is a countable beat
between F3 and C4. F3-C4 = C4-C5.
2. The fourth-doubleoctave test. Mistune C3 so that there is a countable
beat between C3 and F3. C3-C5 = C3-F3.
3. The sixth-seventeenth test. Ab2-F3 = Ab2-C5. This is the one Brekne
described.
4. The octave-nineteenth test. Mistune F2 so that F2-F3 has a countable
beat. F2-F3 = F2-C5.
5. D2-F3 = D2-C5.
6. Mistune C2 so that C2-C5 has a countable beat. C2-C5 = C2-F3.

-----Original Message-----
From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]On
Behalf Of David Ilvedson
Sent: Thursday, September 23, 2004 8:00 AM
To: pianotech@ptg.org
Subject: Re: Octave Tuning


What is the test for a perfect 12th?

David I.



----- Original message ---------------------------------------->
From: Richard Brekne <Richard.Brekne@grieg.uib.no>
To: Pianotech <pianotech@ptg.org>
Received: Thu, 23 Sep 2004 09:25:51 +0100
Subject: Re: Octave Tuning

>BobDavis88@aol.com wrote:

>> In a message dated 9/22/2004 8:13:28 PM Pacific Standard Time,
>> pianotuna@accesscomm.ca writes:
>>
>>     the Accutuner site offers information on octave types here:
>>
>>     http://www.accu-tuner.com/SATIIImanual/aph.html
>>
>> Good, compact chart. However, be aware that the test listed for the
>> 4:2 is incorrect - it should be the 3rd-10th, not the 3rd-17th.


>I think the idea there was that if you tune the 3rd-10th AND the
>3rd-17th such that both the 10th and 17th have the same beat rate speed
>as the 3rd... then you get a just 4:2:1 pair of octaves and double
>octave. The problem with this is that it doesnt yeild a good tuning if
>strictly employed all the way up, and is indeed impossible to executer
>to begin with.  You can try this with Tunelab by directly referencing
>the 4th partial of the lowest note of double octaves and tuning all
>octaves and double octaves directly to that.  You will find that as soon
>as you have progressed chromatically one whole octave and have reached
>your first already tuned single octave that things go astray.  You will
>need to retune the 4:2 that was previously a 2:1... but then that screws
>up what the origional 4:2:1 was...

>Example... C3:C4:C5 get tuned as a perfect 4:2:1. Progress chromatically
>til you are addressing C4:C5:C6.  Now C4 and C5 are already tuned notes
>referenced to C3(4).  But now you want C4(4) = C5(2) = C6(1), which of
>course you cant have.  There is no natural way within the octave tuning
>perspective to deal with this problem, and we are told to just <<smooth
>out>> the difference... a vague and undefined concept at best.  ETDs
>approach the problem by simply spreading the whole treble range evenly
>based on ETD settings and partials information.  However... P 12ths
>tunings simply take care of the whole problem automatically, and a very
>smooth transition from 4:2 to 2:1s is accomplished quite naturally... in
>addition to providing a solid harmonic foundation of just coincidents
>for 12ths throughout the whole treble.

>Indeed.. the P12ths concept completely eliminates the need (or
>desirablitiy) for generated tuning curves to begin with. It represents a
>natural <<built in>> "curve" that is very easily reference either
>aurally or with the help of an ETD used to reference already tuned notes.

>Cheers
>RicB

>_______________________________________________
>pianotech list info: https://www.moypiano.com/resources/#archives

_______________________________________________
pianotech list info: https://www.moypiano.com/resources/#archives