Petrof Inharmonicity

[Frank Weston]

Stephen,

Let me try to make my point more clear for you.  You are proposing that the
difference from zero inharmonicity to typical piano inharmonicity is a
factor in piano tone.  The flaw in your argument is that no piano operates
at zero inharmonicity.  Most modern pianos, high and low tension scales,
operate in pretty much the same envelope of inharmonicity.  In fact the
difference in inharmonicity from unison to unison in the same piano is of
the same order of magnitude as the difference in inharmonicity between
pianos with high and low inharmonicity scales.  Your Mac experiment is the
equivalent of turning the sound volume control from zero to max, noting the
change in the sound, then concluding that changes in volume affect pitch.

What do you have against guns and bullets?

And, by the way, if I were doing the experiment,  I would use my PC running
Windows to measure the inharmonicity of each unison and partials of each
unison for low and high tension scales, then I would vary the inharmonicity
for a given tone in the measured range for that tone and observe the
results.  

Frank Weston 

----------
> From: Stephen Birkett <birketts@wright.aps.uoguelph.ca>
> To: pianotech@ptg.org
> Subject: Re: Petrof Inharmonicity
> Date: Wednesday, March 04, 1998 9:58 PM
> 
> Frank wrote:
> > 
> > Varying the inharmonicity from zero to what is typical for a piano on a
> > tone generator is not exactly like comparing a low inharmonicity piano
to
> > one with high inharmonicity.  What you propose is analogous to
calculating
> > the average speed of a bullet by considering the time it takes to load
the
> > pistol.
> > 
> I really tried here, but fail to see the connection with bullets and
guns.
> 
> The experiment I mentioned has nothing to do with pianos. Simply a
> generated pure spectrum, compared aurally to the same one with a
> reasonable amount of inharmonicity added in. Listen to the two of these
> generated tones and you will hear a distinct difference. Thereby
> confirming that inharmonicity is indeed perceived aurally. 
> 
> You don't need fancy equipment to do this...I did it on a Mac. 
> 
> Stephen
> 
> Stephen Birkett Fortepianos
> Authentic Reproductions of 18th and 19th Century Pianos
> 464 Winchester Drive
> Waterloo, Ontario
> Canada N2T 1K5
> tel: 519-885-2228
> email: birketts@wright.aps.uoguelph.ca