Path: utzoo!utgpu!water!watmath!clyde!bellcore!faline!thumper!ulysses!ucbvax!CORY.BERKELEY.EDU!dillon
From: dillon@CORY.BERKELEY.EDU (Matt Dillon)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Is 29 Khz really the fastest audio playback rate?
Message-ID: <8805190845.AA06593@cory.Berkeley.EDU>
Date: 19 May 88 08:45:08 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 20


:In article <8805171810.AA07554@cory.Berkeley.EDU> (Matt Dillon) writes:
:>	I think everybody is missing a major point here...  If the limit
:>to the audio system is 29KHz/channel, it means that the highest frequency
:>you can get out of the thing is about 14KHz... and that would HAVE to be a 
:>square wave!
:>						-Matt
:
:Matt, this is what the low-pass filter is for. You are correct that the
:maximum frequency that this setup can produce is 14Khz. However on the
:output is a low pass filter that filters out any frequencies above 7Khz
:or so. Ideally this would have a vertical cutoff at 14Khz so that when
:you send a wave of 0xff 0x00 to the output the filter removes all of
:the 'artifacts' above 14Khz and you get a pure 14Khz sinewave out. 

	I stand corrected, though my meaning was more towards 'You can't
have fancy waveforms at 14Khz because you have no room to play with since
you must do it in essentially two samples'.  

						-Matt