Question on timbre

I've been doing some homework. Doty says (p.17 of the Primer) that in the case of a *plucked* string the relative intensities of the partials are inversely proportional to the *square* of the partial number but when the string is *struck* (not plucked) the relative intensities of the partials are inversely proportional to the partial number and not the square of the partial number.

I tested this and I can't detect much of a difference between the sounds produced when either plucking or striking a string. Is Doty wrong?

John.

John,

Odd...I think it would make a difference IF plucked means pulled enough to hit back against the fret board causing a fairly in-harmonic sound to be added as the two collide (IE for the first 30 milliseconds or so). The only time it would matter is if you were "plucking" the string in an incredibly quick manner and the hits caused the 30ms attack dissonances to sort of blend together (very little gap between the dissonances).

I don't think it matters much though...in the same way snare attacks, for example, have the same issue and don't sound bad because the in-harmonicity of the attack is so short. Put it this way, the shorter a period of time dissonance occurs, the less problems it causes. As I understand it, this explains why we call notes that don't match with chords "neighboring tones" in common music theory and play them without much sustain and use "accidentals" (which often don't even match with the key, forget matching with any chords) for even shorter intervals.

Thanks Michael,

if you haven't done so already please take a look at message number 87355 (Subject: From sine waves to complex tones). At this stage I'm assuming that my formulas are correct for sine waves only and am using the same formulas as building blocks for more complex formulas that deal with complex tones (whose harmonics pretty much match the mathematical ideal). I also address two points you made earlier, one about a complex interval (e.g. 473/331) being close to a simple interval (e.g. 10/7), and the other about 47/19 being VERY close to 5/2.

John.

--- In tuning@yahoogroups.com, Michael <djtrancendance@...> wrote:
>
> John,
>
> Odd...I think it would make a difference IF plucked means pulled enough to hit back against the fret board causing a fairly in-harmonic sound to be added as the two collide (IE for the first 30 milliseconds or so). The only time it would matter is if you were "plucking" the string in an incredibly quick manner and the hits caused the 30ms attack dissonances to sort of blend together (very little gap between the dissonances).
>
> I don't think it matters much though...in the same way snare attacks, for example, have the same issue and don't sound bad because the in-harmonicity of the attack is so short. Put it this way, the shorter a period of time dissonance occurs, the less problems it causes. As I understand it, this explains why we call notes that don't match with chords "neighboring tones" in common music theory and play them without much sustain and use "accidentals" (which often don't even match with the key, forget matching with any chords) for even shorter intervals.
>

I hear a difference if I pluck a guitar string or hit it with a dulcimer
hammer.

However, what is more apparent to me is that the dulcimer hammer hit is much
lighter sound over all.

If you need samples I can provide them.

I wonder if perhaps the comparison in mind by Doty was harpsichord vs piano.

On Tue, Apr 13, 2010 at 1:26 PM, john777music <jfos777@...> wrote:

>
>
> I've been doing some homework. Doty says (p.17 of the Primer) that in the
> case of a *plucked* string the relative intensities of the partials are
> inversely proportional to the *square* of the partial number but when the
> string is *struck* (not plucked) the relative intensities of the partials
> are inversely proportional to the partial number and not the square of the
> partial number.
>
> I tested this and I can't detect much of a difference between the sounds
> produced when either plucking or striking a string. Is Doty wrong?
>
> John.
>
>
>
>

On 14 April 2010 00:42, Chris Vaisvil <chrisvaisvil@...> wrote:

> I wonder if perhaps the comparison in mind by Doty was harpsichord vs piano.

Only if you think harpsichords have a less rich spectrum the way it's
reported up-thread.

There's a theoretical distinction proved by Helmholtz. The model is
that a struck string begins with a velocity but no displacement, and a
plucked string begins with a displacement but no velocity. That's how
the relationships come to be so exact. Reality will tend to disagree.

Graham