Frequency shifting of an audio sample....

[mhussainshah]

Hi All ,,

I have an assignment to submit where I have to do the frequency shifting by a factor of 3 or 0.7 . I need to ask if what kind of output should I have after this process .i.e. should the output be as if a man's voice is changed to women or something like that. .

Thanking in anticipation.

 

[FvM]

There is an important difference between frequency shift (which destroys the harmonic relations of a sound, e.g. a voice) and transposing or pitch shift, multiplying the frequency of each spectral component by a factor. You get the latter effect by playing a tape or a record at different speed, which also changes the time axis of the sound. There are musical effects, that transpose a sound but keep the time scale. See Pitch shift - Wikipedia for some examples.

 

[mhussainshah]

hello every one .
here is another relevant question . .. Can any one tell me if I want to control the loudness of selective frequencies what effect should that make on the sound . eg if I wish to increase the amplitude of frequencies below 200 Hz and above 5kHz in an audio sample what kind of effect should that make on the signal.
moreover is there any way I could upload the audio files , original and changed so you maight be able to help in a better way. I am sending the files named 'speech_dft.wav' and the modified file after lodness control named 'output.wav' as a zip file I hope it works .

thanking in anticipation
kind regards

 

[FvM]

Yes, they sound different. So what's the exact question?

 

[mhussainshah]

Yes, they sound different. So what's the exact question?

I intend to ask, if the output sound is behaving correctly . I want to get the concept of amplifying lower and higher frequencies only leaving aside the middle spectrum