[no subject]

[Neil Waterman <neil.waterman@xxxxxxxxxxxx>]

I rarely find something I feel qualified to comment on, but I *DO* know Audacity pretty well... if you pitch-shift in Audacity you will get a (near) exact copy of the original signal multiplied by the pitch shift entered. Nothing more.

If you select a pitch shift factor of x2, then an input signal of 1kHz Sine, becomes 2kHz Sine, with the same for square waves and any other signal in-between.

Personally I find this very unrealistic when applied to voices (I am not a speech or voice specialist, so please forgive my crude comments that follow). Basically all components of the voice signal are proportionally shifted, so certain aspects of the voice becomes unnatural very quickly, with anything more than a small pitch-shift - for example, using the word "sorry", the "sss" component becomes excessively pitched up, whereas in real-life my perception is that the "sss" part of the word "sorry" is pitched fairly closely to the same for people with quite different F0 fundamental pitch to their voice.

The best "voice changer" I have come across is manufactured by TC-Helicon and is the Voicepro unit, used mainly for film voice effects - see http://www.tc-helicon.com/products/voicepro/

Check out the samples. 

I am not affiliated with TC-Helicon by the way. 

- Neil

On Sep 6, 2011, at 12:47 PM, Chuck Larson wrote:

> Hi Brittany,
> Most forms of pitch-shifting shift the fundamental and all harmonic
> frequencies proportionally.  So when you shift the F0 of a male speaker up
> by 4 semitones, it will sound like the voice of a person with a higher
> pitched voice. It will sound very natural and understandable.
> 
> I don't know how audacity or garage band would do the shifting; they may
> do it differently than other commercial devices, but you could easily
> measure the signals before and after to determine which frequencies (F0
> and harmonics) were shifted.
> 
> Best regards,
> 
> Chuck
> 
> 
> 
> On 9/6/11 10:56 AM, "Brittany Guidone" <brittanyguidone@xxxxxxxxx> wrote:
> 
>> Dear List,
>> 
>> To explain more about my original question:
>> 
>> I mainly want to know if "morphing" or "changing" the pitch of a male
>> voice by positive 4 semi tones will change the components of the original
>> male voice (before it was morphed) in a way that will make the two voices
>> have different components or "make up" in comparison to one another,
>> besides the fact that they will have different pitches.
>> 
>> In other words, when the pitch of a voice is changed in audacity or
>> garage band then what other components of the voice are changed (besides
>> the pitch shift)? 
>> 
>> -Brittany 
>> Sent from my Verizon Wireless BlackBerry
>