/Friday, August 25, 2006, 9:27:57 PM, you wrote: /B> I'm looking to do some high sample rate stuff - 500kHz or more - for /B> modulated ultrasonics experiments. Anyone know of a card that will do this ? /B> All I've seen is data aquisition cards that cost silly money, and the sound /B> cards I've found seem to top out at 192kHz. Any pointers appreciated. /Forget using sound cards for this. The main reason to do higher /samplerates is to get a really flat filter response of the /anti-aliasing filters in the audible range. /So these filters would be your main problem if you want to go up in /frequency. /My guess is that you actually need a data-acquisition card for it. /Then you'll need a proper amplifier and transducer for this... /and then the question is how far these waves will actually go through /air, as the higher the frequency the more the wave gets damped in the /air (depending on humidity and temperature). /From what angle are you doing this? What do you try to achieve? /You may want to look at something called audio-spotlights. If I am not /mistaken with that they do something with high frequency sound waves, /where the audible sound is created by interference between two beams /of those... It's a psychoacoustics exercise - trying to generate a new musical experience by combining 'normal' audio with ultrasonics - in a live setting. All the D/A cards I've looked at seem to go well into the MHz range (though I'm confused by the units they use 10MS/s=10Mhz ?), and cost hundereds of pounds. I'm looking for somthing in the middle. Any info on amps/sounders also apreciated, and of course I'd like to use it with linux audio software so an ALSA driver for the device would be nice. Bruce.
