rcd@opus.UUCP (Dick Dunn) (06/19/84)
>...flaming CD's.... > >If they are sooooo good, them how come they naver can produce a >square square wave? Well, neither can oboes or hoboes, bassoons or baboons, guitars, drums, etc. Something that hasn't really been said in this whole square-wave flap is that a CD system COULD be made to produce an extremely good square wave, even at 10 KHz, but it wouldn't make sense to do so. That would be a complete misinterpretation of the data recorded on the CD. >As for the validity of testing auudio equipment with 20 khzsquare waves, >Charles is RIGHT ON. *I* can hear the difference between a 20 Khz >square wave, and a 20 Khz sine wave. The only difference is due to sine >wave components at frequencies > 20 Khz... Wrong-o. I don't care how fine your ears are, you AIN'T gonna hear the difference, because the first component that differs between a 20 KHz sine wave and a 20 KHz square wave is at 40 KHz. Some few lucky individuals may be able to hear a little over 20, but that's about it. (Actually, "unlucky" is more like it; you get to hear a lot of garbage noise that most people are spared.) So am I saying that he's lying, that there's no audible difference? Not at all. I'm sure that if you take that rather substantial 40 KHz component of the square wave and try to hand it to a speaker, it will generate all manner of crap that has more to do with miscreant mechanical resonances of the speaker than with the square wave - particularly if the designer of your amplifier has blessed you with useless DC-to-light frequency response. THAT's what you hear - and if it's important to you, so be it, but it doesn't mean that you've got a bad system. Square waves are useful for some types of measurement, but you have to be careful in interpreting the results of a test with square waves. -- Dick Dunn {hao,ucbvax,allegra}!nbires!rcd (303)444-5710 x3086 ...Cerebus for dictator!
mat@hou5d.UUCP (06/20/84)
Someone said that the lowest difference frequency between a 20kHz sine
wave and a 20kHz square wave is 40kHz. It's not; it's at *60*kHz.
--
from Mole End
Mark Terribile
(scrape..dig) hou5d!mat
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