Klarinet Archive - Posting 000413.txt from 2000/08

From: Tony@-----.uk (Tony Pay)
Subj: Re: [kl] Unloading.....
Date: Wed, 16 Aug 2000 02:06:59 -0400

On Tue, 15 Aug 2000 21:59:04 -0400, bhausmann1@-----.com said:

> At 11:50 PM 8/15/2000 +0100, Tony Pay wrote:
>
> > On Tue, 15 Aug 2000 18:45:58 -0400, bhausmann1@-----.com said:
> >
> > > Digital pianos are stretch-tuned, too.
> >
> > Really?? I suppose that a completely accurate representation of a
> > real piano would include anharmonicity, but it seems to me that that
> > could be advantageously thrown away without changing the perceived
> > tone.
> >
> > Probably it depends on the details of how the sound is synthesised,
> > but isn't the waveform after the attack periodic (even though
> > subject to decay) and therefore certainly harmonic, on such a
> > digital instrument?
> >
> > Or am I talking rubbish?
>
> Not really. Digital pianos reproduce stored digital samples of real
> pianos.

How long is a digital sample? is what my question now becomes. I really
know absolutely nothing about this, about how it's stored, or anything,
so it might be a very silly question, but what goes through my mind is
that if the sample were essentially a wavelength duration, then the
generated sound would be periodic, and therefore harmonic, unlike a
real piano.

'Stretch tuning' is just 'tuning', ie what you have to do to make the
piano 'sound in tune', as best you can. That such 'best tuning' doesn't
correspond to making the lowest partials of all octaves bear a 2:1
relationship is just a fact of life, described technically.

> But because all of it is simply numbers, they can be manipulated
> differently, have corrections/alterations added to change the overall
> tuning, transpose, etc.

Yes.

> > > On some of the better ones you can undo [the stretch tuning]

This is what I don't believe. It has to be built in, surely, one way or
the other.

Either it's anharmonic, but 'best tuned', or it's harmonic, and 'best
tuned':-). We have to ask someone who knows the details.

> > > and use mean-tone or several other variant tuning schemes.
> >
> > I don't understand this bit, anyway. The 'opposite' of mean-tone or
> > other schemes, which are different ways of dividing the octave into
> > semitones, is *equal* temperament, surely.
>
> This starts to get over my head. Perhaps David Renaud, the piano
> tuner who posted earlier, could elucidate?

All I meant was that I think you're confusing two things.

One thing is the effect of anharmonicity on how pianos are tuned,
particularly at the extremes of the range.

The other has nothing to do with that, but is something that applies to
any instrument, harmonic or not. (It applies equally to an organ, say,
which produces sounds that are sustained, and therefore both periodic
and harmonic.) It's possible to use different tuning schemes within one
octave that make certain keys, particularly chords in those keys, sound
better in tune at the expense of other keys.

It's *that* that is programmable on modern digital instruments. By
default, they're tuned to equal temperament, which doesn't favour any
one key, or group of keys, above any other.

Tony
--
_________ Tony Pay
|ony:-) 79 Southmoor Rd Tony@-----.uk
| |ay Oxford OX2 6RE GMN family artist: www.gmn.com
tel/fax 01865 553339

---------------------------------------------------------------------
Unsubscribe from Klarinet, e-mail: klarinet-unsubscribe@-----.org
Subscribe to the Digest: klarinet-digest-subscribe@-----.org
Additional commands: klarinet-help@-----.org
Other problems: klarinet-owner@-----.org