trantow@csd4.milw.wisc.edu (Jerry J Trantow) (03/24/89)
Put LineEaters on a diet. Has anyone out there used volume modulation to get sound better than simply using 8 bits. What I have in mind is using both volume and waveform to increase the quality of sound. I had a little hack running about a year ago where I took some 12 bit samples (Curly, Larry, and Moe) calculated a volume envelope and waveform and played the samples thru the audio device. I was fairly disappointed because it seems like the volume and waveform were not changing simultaneously. For a vivid demonstration of this, take any 12 bit number and factor it into a 6 bit (volume) and 8 bit (waveform) number. If they both changed simultaneously it should work. (Didn't work for me.) I think what is happening is one channel changes before the other and a one bit change in volume multiplied by the waveform is a pretty big error. I am interested for a couple of reasons in pulling this off and will go so far as to put in a S/H if I have to. (Sample and Hold) I would appreciate any comments. I let someone use my hardware manual two months ago and haven't gotten it back yet so I appologize that I have not verified this with the book. _____________________________________________________________________________ Jerry J. Trantow | I love the man that can smile in trouble, 1560 A. East Irving Place | that can gather strength from distress, Milwaukee, Wi 53202-1460 | and grow brave by reflection. (414) 289-0503 | Thomas Paine _____________________________________________________________________________
jimm@amiga.UUCP (Jim Mackraz) (03/28/89)
In article <1683@csd4.milw.wisc.edu> trantow@csd4.milw.wisc.edu (Jerry J Trantow) writes:
)Has anyone out there used volume modulation to get sound better than
)simply using 8 bits. What I have in mind is using both volume and
)waveform to increase the quality of sound.
Sam Dicker, author of audio.device, implemented this a couple of years
ago. I think it is included in some form with the Mimetics sound digitizer,
you'll have to contact them for more info.
They used to play a CD straight through, digitize, compand, out to analog,
and it sounded great. I would love to see this technology make it into
common use, if it's as nice as I remember.
jimm
--
Jim Mackraz, I and I Computing "Like you said when we crawled down
{cbmvax,well,oliveb}!amiga!jimm from the trees: We're in transition."
- Gang of Four
Opinions are my own. Comments are not to be taken as Commodore official policy.