P 12ths revisited

[Peter Joris]

Thanks Ric,

I tried to contact you privatly before, but my mail probably did not reach
you.

I use your procedure from a while back that I found in the archives and I
have a few fans that only accept this tuning method, so....

If your template Is different from what was described at that time, I would
like to receive it aswell.

Kind regards,
Peter Joris

-----Original Message-----
From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf
Of Richard Brekne
Sent: Saturday, April 02, 2005 00:25
To: pianotech@ptg.org
Subject: P 12ths revisited

Hi Folks

Thought I'd share with you a few thoughts and experiences I've had after 
a couple years now of using Tunelab to execute a P12ths tuning.  As some 
of you might remember I used Tunelab 97's numerical curve editor to 
construct a tuning curve from A1 to F6 with all notes set at the 3rd 
partial. From D3 to F6 12ths were all spaced so that their first order  
coincident frequecies are identical, and I opted for 6:3 octaves in the 
bass.

One of the neat things this allows for, and I think is a great aid in 
understanding tuning from a coincident partials perspective, is that one 
can see exactly the kind of information the aural tuner uses in very 
much the same fashion.
By way of example say you have the display on D4.  Both D4 and A5 are 
tuned directly from this frequency. That is to say the 3rd partial of D4 
and the 1st partial of A5 are tuned equal yielding a perfect 12th. But 
at the same time you are able to veiw the 4:2:1 relationship of the 
double octave A3, A4, and A5.  This because both A4 and A3 also share 
this coincident.  A3-D3 is a 4th, (4:3 coincident), and D3-A4 is a 5th,( 
3:2 coincident).

In tuning by ear if you would use any one of a few tests to confirm 
something between a 6:3 and a 4:2 relationship for A3-A4, and for A4-A5 
a somewhat tighter octave. All the while you want to maintain the wide 
A3-D4 4th and narrow D4-A4 5th.
Using tunelab set to the 3rd partial of D4 one can readily see exactly 
whether these relationships are achieved or not.  This is really handy 
as you tune upwards as one can quickly identify any note that may have 
moved just a bit. One is able to maintain  a 4:2:1 relationship that 
leaves the 4:2 essentially pure with the fundemental of the top octave 
just wide.  As you progress upwards you can visually confirm an even 
convergence towards a just 4:2:1 for the entire top 12 notes.  All the 
while maintaining a all 12ths pure.

I usually start at D3 and tune D2, D3, and A4 to this frequency. This 
gives me a pure 6:3 octave for D2-D3 and a pure 12th for D3-A4.  Moving 
chromatically upwards, by the time I get to D4 I'm able to also start 
looking at the octave relationship D4-D3 to make sure it D3 hasnt moved 
on me, that it stays at a just 6:3.  As I move upwards I expect this to 
gradually narrow, which is also easy to see watching the same D4 third 
partial.

So for just one note.  D4. I am able to visually confirm my aural 
intentions for the notes D3, A3, D4, A4, and A5 which are the 6:4:3:2:1 
coincidents respectively.  And I have this ability for every note in the 
curve.

Using this as a template for an aural tuning allows for a very concious 
and precise execution of a tuning. It also is a great teacher. Just do 
this a few tens of times and see what lights go on in your mind about 
tuning in general.  It also helps develope your aural skills as you are 
getting direct coincident partials visual feedback.
Anyways... I hope this is of interest to some of you.  Anyone who wants 
the P12th template I use can email me and I will send it to them. You 
can create your own using tunelab 97 only, but the curve once created 
can be used in any version of Tunelab

Cheers
RicB



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