# Male and female voice spectrum

I have a set of data which consists of male and female voices. They are pronunciation of a same sentence. What's the appropriate method for getting an average spectrum for the male and female voices separately and comparing them? I can take fft of each voice but what's the next step to get an average spectrum? Also Welch's method can be applied to one voice each time. I know that this is in fact a random process and each of the voices is a realization but how can we estimate PSD using these realizations?

Edit: Thanks to Marcus Müller, here is the result which I've got using $$\frac{1}{N}( |\text{FFT}(x_1)|^2 + \dots + |\text{FFT}(x_n)|^2)$$ And here is the code:

  male = fft(k.');  %k: male voices
male1 = (abs(male)).^2;
male2 = sum(male1.')/36; %36: number of male voices

female = fft(s.');  %s: female voices
female1 = (abs(female)).^2;
female2 = sum(female1.')/13;    %13: number of female voices

plot(f , fftshift(male2) , f , fftshift(female2))
legend({'male','female'},'Location','southwest')


It would be really nice to see the other ways for estimation of PSD in this case.

• why do you think that Welch's method wouldh't work? It's the standard method of this sort of thing. Dec 19 '20 at 19:13
• @Hilmar It's straightforward to apply it on a single voice using pwelch` command but I don't know how to apply it on all of the voices. Dec 19 '20 at 19:20
• @S.H.W sounds like you're asking us how to calculate an average? Dec 19 '20 at 20:55
• @MarcusMüller I really don't know how to get a good estimation of PSD for this random process using different voices. Dec 19 '20 at 21:09
• well, so calculating the average would be a start, wouldn't it? Otherwise, there's really a big load of literature on classification. It's kind of a popular application of artifical neural networks, too, but classical classifiers (see what I did there?) is also something you might want to look into. Dec 19 '20 at 21:58