I recall something similar from long ago. However I routinely use audio filtering on my DX recordings in playback mode, and even with a female voice, I rarely let anything through above 3 kHz, and it's very readable.
I still maintain the issue is economics, not audio intelligibility. That's just a convenient cover. On Wed, Apr 23, 2014 at 12:58 PM, T. Hills <"thills"@sio.midco.net> wrote: > I remember reading a paper from NASA about understandability and frequency > when I was in college (Many Moons ago). > > I think the numbers I state are the same as in the paper but could be off > but the general idea is the same. > > It was found that the understandability of the average male voice was not > decreased when frequencies above 3000Hz and below 300Hz were filtered out > but for the "average woman" it was 400Hz and 4500Hz respectively. The > Author of the paper suggested a switchable voice filter that could be set > for male or female Operators/CapComs/Astronauts. I sometimes wonder if men > tending to lose hearing on the higher end first isn't a survival tactic ;) > > This wasn't an issue until the Shuttle for the US and if I recall it was > suggested that the Soviets had been using either a switchable filter or a > wider one since the early days of human space flight. > > Tim Hills > Sioux Falls, SD > > On 4/23/2014 11:02 AM, Russ Edmunds wrote: > >> I'm puzzled as to why 3 kHz isn't good enough. I can't say that I've >> heard any TIS stations which >> were functioning properly which were difficult to hear. I'd guess this >> might be an economic issue >> relating to the added costs of filtering, in which case a change to 5 kHz >> won't change anything. >> >> >> Russ Edmunds >> 15 mi NNW of Philadelphia >> Grid FN20id >> <[email protected]> >> >> >> > > _______________________________________________ > IRCA mailing list > [email protected] > http://montreal.kotalampi.com/mailman/listinfo/irca > > Opinions expressed in messages on this mailing list are those of the > original contributors and do not necessarily reflect the opinion of the > IRCA, its editors, publishing staff, or officers > > For more information: http://www.ircaonline.org > > To Post a message: [email protected] > > -- Russ Edmunds 15 mi NW Phila Grid FN20id <[email protected]> AM: Modified Sony ICF2010's (2) barefoot w/whip FM: Yamaha T-80 & T-85, each w/ Conrad RDS Decoder; Onkyo T-450RDS; Tecsun PL-310 ( 2); modified Sony ICF2010 w/APS9B @ 15'; Grundig G8 w/whip; modified Sony ICF2010 w/whip _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [email protected]
