For most speech formants there is a gap above about 1000 hertz. If one is depending on only the F1 formant, then a cutoff of about 1000 hertz is appropriate. Another rule that applies is the 450,000 (or 500,000) rule. Multiply the highest frequency by the lowest frequency and the product should be one of those two numbers for a balanced response. So, if the upper cutoff is 1 KHz, then the lowest would be 500 hertz. Such a response is slicing the F1 formant which is typically 1 KHz wide.
Sent from my iPad > On Jul 1, 2018, at 11:19 AM, Don Wilhelm <donw...@embarqmail.com> wrote: > > Clay, > > We are not talking about shifting the pitch of the signal by 50 Hz, we are > talking about enlarging or restricting the pitch at only the low frequency > end or the high frequency end by 50 Hz. > The LowCut and HiCut controls are like the Bass and Treble controls on a car > AM/FM radio. Think what would happen if your radio's Bass control were > reduced by 100 Hz instead of 50 Hz - the difference is insignificant. > > Oh yes, the Bass and treble controls on that AM/FM radio are not calibrated > for precise frequencies like the K3 HiCut/LoCut controls are, so we "use our > ears" to determine what is best. We should do the same for the > K3/K3S/KX3/KX2. > > There is no communications effectiveness for frequencies below 300 or 400 Hz > (0.30 to 0.40) on the low cut side, and there is little voice recognition in > that range. The effective range for voice recognition begins at about 500 > Hz, and extends to about 2600 Hz. That is for recognizing the > characteristics of a particular voice pattern we are familiar with. For > communications effectiveness, we can reduce the listening range to 500 Hz to > 1700 Hz and still communicate with clarity. > > 73, > Don W3FPR > >> On 7/1/2018 10:20 AM, Clay Autery wrote: >> I don't have "perfect pitch", but do have extensive music experience if that >> matters.... >> Single tone, single voice, or an orchestra.... 50Hz off freq. is enough to >> make me want to drill holes in my head. I can easily distinguish below 10 >> hz, and sometimes 5 Hz.... and my ears are damaged from years of rotary-wing >> flight/maintenance, small (and larger) arms reports. >> That said...when using Lo/High/Shift/Width, the 50Hz resolution is being >> used in a "relief from distractor" mode, so it is less of an issue, but >> there HAVE been times that I wished for a slightly finer resolution. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to w...@w2xj.net ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
