Electronic pianos and inharmonicity

[Frank Weston]

I have used TuneLab to check out a high end Technics digital piano, and
there is indeed inharmonicity.

Frank Weston

-----Original Message-----
From: Robert Scott <rscott@wwnet.net>
To: pianotech@ptg.org <pianotech@ptg.org>
Date: Monday, November 08, 1999 2:42 PM
Subject: Electronic pianos and inharmonicity


>Diane Hofstetter wrote:
>
>>A digital piano has only a fraction of the mix of
>>harmonics that an acoustic piano does. The samples are relatively short in
>>duration (frequently only a few seconds) and then the sample is looped
over
>>and over for greater sustain so you hear only the harmonics from the first
>>attack of the key.
>
>This business of the sound being "looped over and over" raises some
>difficulties with respect to inharmonicity.  You can't have both in a
>sampled electronic instrument.  If the sampled sound is repeated, even
>once, then the phase of all the partials would have to be the same at the
>beginning and at the end of one sample period.  If not, then the
>discontinuity would be clearly heard as a "click" at the transition
>point.  Therefore I have to conclude that electronic pianos either do
>not model inharmonicity or else they do not recycle samples.
>
>I am certain that the low-cost keyboards have zero inharmonicity.
>But I don't have access to any of the really expensive models.
>If there is anyone who has access to a really fancy electronic
>piano and who also has an SAT or RCT or TuneLab, then simply
>measure the inharmonicity (or get the FAC numbers) from such
>an instrument.  I would like to hear about any such instrument
>with non-zero inharmonicity.
>
>-Robert Scott
> Ann Arbor, Michigan
>
>
>