Subject: Re: lopsided tones. From: christopher jette <christopherjette@xxxxxxxx> Date: Tue, 18 Aug 2009 11:44:18 -0500 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>--00504502c070c4ec3104716d3ad4 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit 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@xxxxxxxx> 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 > -- www.cj.lovelyweather.com christopherjette@xxxxxxxx 617.869.3968 --00504502c070c4ec3104716d3ad4 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable One question of clarification. When you say the positive period of the wave= form is larger, I assume you mean that you are employing a longer wave peri= od (read: linear distance in a waveform display), as opposed to vertical di= stance from the zero crossing, in comparison with the negative section.=A0 = Is that correct. <br> <br>If the wave period is longer, you are creating a period that is of a di= fferent 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). <br> <br>Cheers~<br>Christopher<br><br><div class=3D"gmail_quote">On Mon, Aug 17= , 2009 at 2:41 PM, Ranjit Randhawa <span dir=3D"ltr"><<a href=3D"mailto:= rsran@xxxxxxxx">rsran@xxxxxxxx</a>></span> wrote:<br><blockquote c= lass=3D"gmail_quote" style=3D"border-left: 1px solid rgb(204, 204, 204); ma= rgin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Dear List,<br> I have been experimenting with a 100hz tone, where the positive half sinuso= id of the period is larger than the negative, the phase is however is not c= hanged. Speech seems to have this profile of larger positive pulses as comp= ared to the negative, hence my interest. Applying fft to such a signal, I g= et 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 o= n top of it, not what fft seems to indicate. My assumption was that the inc= reased dc component would not be heard, and I would hear an increase in lou= dness of the 100 hz. However, the base 100hz loudness does not seem to chan= ge as I increase the area under the positive sinusoid, but the flutter does= . Any history or explanation would be most welcome.<br> Thanks and regards,<br> Randy Randhawa<br> </blockquote></div><br><br clear=3D"all"><br>-- <br><a href=3D"http://www.c= j.lovelyweather.com">www.cj.lovelyweather.com</a><br><a href=3D"mailto:chri= stopherjette@xxxxxxxx">christopherjette@xxxxxxxx</a><br>617.869.3968<br> --00504502c070c4ec3104716d3ad4--