[sdiy] harmonics & vibrato

[Scott Evans, Gen Mgr]

Right. Remember the vibrating string model: A full vibrational period is 
the fundamental. At twice that frequency, the second harmonic sounds, as 
it is half the wavelength of the first. And so on with the third, fourth...

If the string is shortened, both the fundamental and the entire harmonic 
series are rasied proportionally, maintaining the 1 to 2, 1 to 3, etc. 
relationships that are in the normal harmonic series. The vibrato is 
really a change in pitch.

You are correct in that the shortening of the string has a "greater" 
effect on the harmonics, as they are raised in frequency faster than the 
fundamental. However, since the perception of pitch is a log scale, the 
proportions remain.

If fundamental is 400hz, and the vibrato moves this from 390hz to 410hz, 
the 800hz second harmonic would move from 780hz to 820hz maintaining the 
harmonic relationship of twice the fundamental.

I hope I am explaining this appropriately to your question.

Scott (who would rather frequency shift than pitch shift any day)
---------------------------------------------------------
Tim Ressel wrote:
> Hey Scott,
> 
> Well, as the finger moves back and forth it shortens
> the effective length of the string. The harmonics take
> less of a fraction of the length of the strng per
> wave, so it follows that the shortening would have a
> greater effect on the harmonics. Does that sound
> right?
> 
> =-= tr
>