[pianotech] ETD stretch vs pure (octaves)

[James Johnson]

Aural tuners don't tune "pure" octaves.  I guess we use "stretch factors", 
we just don't call them that. When I learned to tune, one of the most 
difficult things to master was how to stretch the tuning, both in the treble 
and in the bass, and how to make that stretch match the inharmonicity of 
each piano, big or small.  The answer to your question is that aural tuners 
use beats and test intervals to give them the stretch for each individual 
piano.  The octaves in the treble of a spinet piano will be very wide 
whether you tune with an ETD or by ear.   I don't tune octaves in the 
treble, I accept them after I use all my other tests.  The double octave 5th 
is the primary interval which I use to determine stretch in the top couple 
octaves.

Jim
----- Original Message ----- 
From: "Duaine & Laura Hechler" <dahechler at att.net>
To: <pianotech at ptg.org>
Sent: Friday, November 13, 2009 7:25 AM
Subject: [pianotech] ETD stretch vs pure (octaves)


> This may seem like a silly question but ....
>
> At least Cybertuner has stretch factors built-in. Do you aural tuners do
> stretch factors?
>
> How do you tune "pure" octaves with a "stretch" factor - this seems
> oxymoronic.
>
> Duaine
>
> -- 
> Duaine Hechler
> Piano, Player Piano, Pump Organ
> Tuning, Servicing & Rebuilding
> Reed Organ Society Member
> Florissant, MO 63034
> (314) 838-5587
> dahechler at att.net
> www.hechlerpianoandorgan.com
> --
> Home & Business user of Linux - 10 years
>
>
>