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Re: lopsided tones.



One question of clarification. When you say the positive period of the waveform is larger, I assume you mean that you are employing a longer wave period (read: linear distance in a waveform display), as opposed to vertical distance from the zero crossing, in comparison with the negative section.  Is that correct.

If the wave period is longer, you are creating a period that is of a different length and therefore not 100Hz, but a slightly different frequency. My understanding is that he two tones are interfering, hence the flutter (sidebands both above and below the 100Hz tone).

Cheers~
Christopher

On Mon, Aug 17, 2009 at 2:41 PM, Ranjit Randhawa <rsran@xxxxxxxxxxx> wrote:
Dear List,
I have been experimenting with a 100hz tone, where the positive half sinusoid of the period is larger than the negative, the phase is however is not changed. Speech seems to have this profile of larger positive pulses as compared to the negative, hence my interest. Applying fft to such a signal, I get an increase in magnitude for the 100hz component, and an increase in the dc component. What I hear however is the basic 100hz tone, and a flutter on top of it, not what fft seems to indicate. My assumption was that the increased dc component would not be heard, and I would hear an increase in loudness of the 100 hz. However, the base 100hz loudness does not seem to change as I increase the area under the positive sinusoid, but the flutter does. Any history or explanation would be most welcome.
Thanks and regards,
Randy Randhawa



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