Re: headphones + FCT + strange phenomenon (Eckard Blumschein )

Subject: Re: headphones + FCT + strange phenomenon
From:    Eckard Blumschein  <Eckard.Blumschein(at)E-TECHNIK.UNI-MAGDEBURG.DE>
Date:    Wed, 23 Oct 2002 17:40:21 +0200

Perhaps, provides valuable information on headphones, etc., too. Please find links to several adjacent forums like headwize via my new address The reason for me to have a private address was publicly uttered distrust in my suggestion that ambiguity, redundancy and non-causality of the traditional Fourier transform can be overcome by simply using the well known one-sided Fourier cosine transform (FCT) instead of Fourier Transform (FT) in case of signals f(t) being limited to the past, that is, being limited to positive elapsed time t>0. After fierce discussion with physicists I feel, I am correct. Calculation of FCT is no problem at all because you will find largely the same correspondence table as for FT. The first and major difference is the range of integration. While FT spans from minus infinity to plus infinity, FCT and its inverse are restricted to positive values only. Secondly, the FCT is just a real part of an integral with the same exponential kernel as for FT. However this does not matter because its imaginary counterpart, the Fourier sine transform (FST), would relate to quite a different original f(t) with odd continuation on the mirror plane. I would also like to ask whether someone else experienced the same strange phenomenon: I looked at spatial orientation of our cochleas. Axes are forward directed as are our eyes, too. Accordingly, sudden rotational movement of my head does not elicit any noticeable auditory sensation as long as axis of this rotation does not coincide with axes of the cochleas. I may move my head as fast as I can to the left as well as to the right, also up and down. However, as I expected, I hear for a moment a high pitched tone if I rapidly tilt my head down toward my right shoulder. To the opposite side the pitch tends to be apparently different. Admittedly, I am suffering from tinnitus quite a little bit. Eckard At 10:47 23.10.2002 -0400, Robert E. Remez wrote: >Dear list: > >Have you calibrated a Beyerdynamic DT770 headphone set? I would be >grateful to know of the measures, specifically, for converting AC >voltage to SPL. > >Thanks, > > Robert Remez > >-- > >============================================================= >Robert E. Remez 212.854.4247 office >Ann Whitney Olin Professor 212.854.3601 fax >Department of Psychology 212.854-2069 Department >Barnard College Email: remez(at) >3009 Broadway Home Page: >New York, New York 10027 >

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