Call for scaling spreadsheets

[Jason Kanter]

This aspect of acoustics is also new to me. Having spent a lot of time in 
Africa, I know that elephants use very low frequencies ("rumble") to 
communicate across great distances. That and other first-hand experience 
indicate that the upper partials do not travel as well. Surely there is a 
mathematical relationship between distance and perceived frequencies. Is 
this because of friction in the air, or something about the shortness of the 
wavelength? In any case, it occurs to me that perhaps there may be a kind of 
doppler shift with distance -- the inharmonicity "constant" may vary with 
distance (and possibly with the composition of the air -- e.g. humid air may 
transmit sound differently from dry air.
Not that this would affect scale design, really. But it seems to bear on the 
phenomenon of perceived inharmonicity.

Thots?

jk
----- Original Message ----- 
From: "David Love" <davidlovepianos at comcast.net>
To: "'Pianotech List'" <pianotech at ptg.org>
Sent: Friday, September 29, 2006 11:00 AM
Subject: RE: Call for scaling spreadsheets


>I wouldn't think too long about it--unless it's to more clearly define
> terms.  Higher tension scales such as found on concert instruments 
> "project"
> much better than low tension scales.  The higher tension scales will have
> lower inharmonicity.  Tuning the upper treble sharp has little to do with
> inharmonicity or projection.  It may, however, help with the top being
> perceived as flat when heard from a distance.
>
> David Love
> davidlovepianos at comcast.net
> www.davidlovepianos.com
>
> -----Original Message-----
> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On 
> Behalf
> Of Ric Brekne
> Sent: Friday, September 29, 2006 10:34 AM
> To: pianotech at ptg.org
> Subject: Call for scaling spreadsheets
>
> Hi Stéphane
>
> This is interesting.  I hadnt thought along the lines of overall
> projection being linked to overall inharmonicity.  Yet some of the
> tuning discussions we've had through the years here are perhaps not too
> far removed from that kind of thinking.  For example it is ofte times
> mentioned that stretching the top more then is up front comfortable can
> result in better projection through a large hall.
>
> I'd like to hear more of your thinking about along these lines.
>
> Cheers
> RicB
>
>     Sure.  But when I meant projection, I didn't mean loudness.  You have
>    pianos that sound very loud at 1 or 2 meters around them, but the
>    loudness
>    decreases rapidly with the distance.  Others (I have a particular and
>    amazing straight strung 1873 Bechstein in mind) seem to have some
>    obscure
>    acoustic feature that makes them carry their sound way farther
>    effortless, a
>    bit like some venues acoustics (I think of the Concertgebouw in
>    Amsterdam,
>    Netherlands,  here) where at the very back of the place, you still
>    hear the
>    tongues in the throats of the singers.  I believe this has to do with
>    inharmonicity, not only with loudness.  Harmonic sounds can (do)
>    cancel each
>    other.
>
>    What do you think ?
>
>    Stéphane Collin.
>
>
>
>