On Saturday 24 November 2007, Vladimir Mosgalin wrote: >Hi Gene Heskett! > > On 2007.11.23 at 11:56:56 -0500, Gene Heskett wrote next: >> >Anyway, in analog mode, are you sure there is no option to switch off >> >bandwidth filter? >> >> No one in their right mind would want to do that as the aliasing would >> drive you up a wall. The other delay distortions the filter might give >> are 100's of times more tolerable to listen to. > >Er.. I meant in 96khz mode. Or in 48khz. I understood original letter as >if the card has that bandwidth limitation on any sampling frequency, and >this is a problem. Of course at 44.1khz D->A conversion it's desired to >have something like that. Not that it matters in digital mode, since >it's up to DAC filters. > No it isn't, once the aliasing is in the digital domain, it cannot be filtered away because its now part of the 'active bandwidth', so the filters really do need to be 'brick wall', at slightly less than 1/2 the sampling frequency. >PS a bit of OT: I'm 24, and I barely hear 18khz (in headphones), unless >it's VERY loud - I can hear only up to 17500-17800 clearly at average >volume level. Is there something wrong with my ears or it should be like >this? That's probably somewhere near normal and might depend slightly on how much wax buildup is in the ear canals, and on the headphones themselves, I see a lot of boxes on the shelves proclaiming 30hz-18khz. I'd be willing to bet that you can walk into some business with an ultrasonic doppler based burglar alarm running, and feel it. Those things can put several watts into the air at around 40 kilohertz. The false alarm rates with those were pretty high, specially if they could see a big picture window, which flexes in the wind enough to trigger the alarm. I don't think they are as popular now as back in the early 80's though, for that reason. I don't think I'd worry too much about it just yet. I'm not wearing any aids and I'm getting along fairly well yet. -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Mal: "So Shepard says to a Companion, "Well, a good goat will do that." " --Episode #5, "Safe" ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
