If I had known the answer involved Fourier transforms (and I guess I
should have) I wouldn't have asked the question. :-)
Chuck Norcutt
ws wrote:
> The square root of the inverse Hilbert transform convoluted with the
> hypotenuse of the frequency, integrated over +-infinity time and you can
> show Why this is correct. :-)
>
> Actually the Fourier transform of a square wave shows odd harmonics that
> decrease in frequency, so a reasonable approximation requires summing
> a certain number of these harmonics, to recreate a square wave, But probably
> more import is the phase shift introduce with lower bandwidth systems.
>
> http://homepages.inf.ed.ac.uk/rbf/CVonline/LOCAL_COPIES/OWENS/LECT4/node2.html
>
> I do not know of any experimental listening tests of this, and I don't think
> I can
> hear past 12Khz these days. At one time, I could hear 16KHz sine wave
> but my wife doesn't think I can hear at all. Maybe she just needs more
> bandwidth? Unfortunately bandwidth usually means a lot of work.
>
> I just wish someone would inform the mobile phone developers that
> too much compression turns voices into noise.
>
> Wayne - say what?
>
> At 06:20 PM 1/24/2009, you wrote:
>> Why?
>>
>> Chuck Norcutt
>>
>> Ken Norton wrote:
>>
>>> It takes 160kHz of bandwidth to pass a a 20kHz square wave. Only 20kHz to
>>> pass a 20kHz sine wave.
>> --
>
>
>
>
--
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