quote:
Originally posted by hardc0re
i tested.. i can hear 18kHz but 19 & 20 i cant 
To statr with, make sure your speaker set can actually play up to 20KHz frequencies. The only way to determine this is to look up the specs of your speakers (or to measure the sound played by it, but I recon you don't have a calibrated frequency analyzer at hand)...
Some speakers simply will not play anything of a certain high frequency. So you might think you can't hear the frequency, while in fact the speaker isn't producing any sound at all...
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