a good solution could be to use a slow sweep and a tracking algorithm to
follow the moving spectral peak. Then Hz,dB values can be easily plotted in=
Excel. I usually use this method to check frequency response of a-a filters=
.
Gianni
At 09.14 02/03/2004, you wrote:
>Dan, you wrote,
>
> > Raimund, you wrote,
> >
> > >I will use a sine sweep played through a portable CD player. A sine sw=
eep
> > >would probably better suited because it could be difficult to distingu=
ish
> > >between emitted noise and the ambient/self noise.
> >
> > I dunno, it's harder to interpret, harder to display a sweep. I'd use
> > pink noise turn off the source for part of each setup to get a
> > recording of the ambience. Then you ignore the parts of the response
> > where you don't have 10 dB or better s/n.
>
>Yes, there are various approaches for measuring frequency responses. The
>noise approach is definitely easier to interpret. The sine sweep approach=
>would
>require spectrographic analysis. Though it would even be possible to use a
>simple spectrum display for analyzing a short linear sine sweep (as long
>as the
>spectra are computed from a single sweep and without applying any weightin=
g
>windows as Hamming or something similar).
>
>So, perhaps I will prepare a CD that contains both sine sweeps and short
>noise bursts.
>
>Raimund
>
>--
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>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
--------------------------------------------------------------
Gianni Pavan
Email
Centro Interdisciplinare di Bioacustica e Ricerche Ambientali
Universita' degli Studi di Pavia
Via Taramelli 24, 27100 PAVIA, ITALIA
Tel +39-0382-507874
Fax +39-02-700-32921
Web http://www.unipv.it/cibra
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