AW: [AUDITORY] question about overtones

[Sascha Fagel <sascha.fagel@xxxxxxxxxxxx>]

Dear Tom,

at least in speech and singing the sound characteristics of the primary
source (glottis) is of importance. The output spectrum is a combination of
the glottis spectrum and the vocal tract filter. The glottis produces
something like a sawtooth
f(t) = sin (t) + 1/2 sin (2t) + 1/3 sin (3t) + ... with a bit less high
frequencies.
The vocal tract has an overall relatively flat spectrum with again less high
frequencies. But there are local maxima and minima due to the formants (as
Gustavo has mentioned). You can find some details in Douglas O'Shaughnessy's
"Speech Communications - Human and Mashine".

Best regards
Sascha

******************************************
Dr. Sascha Fagel
Technical University Berlin
Communication Science
Secr. TEL10-1
Ernst-Reuter-Platz 7
10587 Berlin
Fon +49(30)314-24527
Fax +49(30)314-79883
Email: sascha.fagel@xxxxxxxxxxxx
http://fourier.kgw.tu-berlin.de/fagel.html
******************************************

-----Ursprungliche Nachricht-----
Von: AUDITORY Research in Auditory Perception
[mailto:AUDITORY@xxxxxxxxxxxxxxx]Im Auftrag von Luis Gustavo Martins
Gesendet: Donnerstag, 17. November 2005 12:27
An: AUDITORY@xxxxxxxxxxxxxxx
Betreff: Re: [AUDITORY] question about overtones


Dear Tom,

The relative amplitude of the overtones (i.e. harmonics) of a speech or a
musical instrument sound is mainly defined by the resonant frequencies of
the vocal tract (for the speech case) or by the musical instrument
construction parameters (size, shape, materials, etc). This has an impact on
the perceived timbre of a sound.

These spectral resonances (also known as the peaks on the sound's spectral
envelope) are known as formants, and they have an important influence on the
timbre and "quality" of the sound (e.g. The first two formants of a speech
signal have a big impact on the production of the different vowels, while
higher order formats determine the register or the timbre quality of the
voice).

Hope it helps,

Cheers,

Gustavo

---------------------------------------
Luis Gustavo Martins
lmartins@xxxxxxxxxxxxx
www.inescporto.pt/~lmartins
INESC Porto
Portugal
www.inescporto.pt
---------------------------------------

> -----Original Message-----
> From: AUDITORY Research in Auditory Perception
> [mailto:AUDITORY@xxxxxxxxxxxxxxx] On Behalf Of Tom Lee
> Sent: quinta-feira, 17 de Novembro de 2005 0:59
> To: AUDITORY@xxxxxxxxxxxxxxx
> Subject: [AUDITORY] question about overtones
>
> Dear list,
>
> Does anyone have information about the amplitude
> relation between a tone and its overtones? What I mean
> is, if I have some frequency and I want to generate
> its natural overtone series, how loud do I make the
> overtones in relation to the fundamental? Thanks in advance!
>
> -Tom
>
> Live by the foam sword; die by the foam sword!
> http://www.yale.edu/freeduel
>
> Keep the jukebox swinging.
>
>
>
>
> __________________________________
> Yahoo! Mail - PC Magazine Editors' Choice 2005
> http://mail.yahoo.com