# Re: Spectral resolvability of harmonics

```OK here's a little start ... I have attatched simple scripts which should
work in 'octave' http://www.che.wisc.edu/octave  (perhaps Matlab too -
don't know though - if you run Matlab please inform your parents)

The scripts will find ERBs from Frequencies and vica versa.

Once in the ERB domain harmonics are equidistant in range (in theory any
way). But I'm sure someone else will want to expand on this point ....

There are some papers by Greenwood for example which will tell you that
what is reguarded a harmonic is different for different mammals ...

Matt

On Fri, 29 Sep 2000, Annemarie Seither-Preisler wrote:

> Dear List,
>
> I am looking for an adequate method to determine the frequency limit
> separating resolved from unresolved harmonics in a complex tone, when f0
> is given.
> I am interested in empirical data, simple algorihms based on ERBs, as
> well as in program listings (Fortran, C, Matlab etc.).
>
>
>
> Annemarie Seither-Preisler
>

```
```function freq=erb2freq(erb)

%# ERB2FREQ - Finds the freq. in Hz for an erb.

%# references
%#[1]  ``A Model for the Prediction of Thresholds, Loudness, and Partial
%#        Loudness'' Moore B.C.J., Glasberg B.R. and Baer T., Journal of the
%#       Audio Engineering Society, vol. 45, no. 4, April 1997, pp.224-40.

c1=24.673;
c2=4.368;
c3=(2302.6/(c1 * c2));

freq=1000.0 * (10.^(erb/c3) - 1.0) / c2;
return;
```
```function erb=freq2erb(freq)
%# FREQ2ERB - Finds the erb for a freq. in Hz

%# references
%#[1]  ``A Model for the Prediction of Thresholds, Loudness, and Partial
%#        Loudness'' Moore B.C.J., Glasberg B.R. and Baer T., Journal of the
%#       Audio Engineering Society, vol. 45, no. 4, April 1997, pp.224-40.

c1=24.673;
c2=4.368;
c3=(2302.6/(c1 * c2));

erb=(c3*log10((c2 * freq/1000.0) + 1.0));
return;
```