Hey Guys and Gals:

Something you might be interested in...

A couple of years ago I got into a (heated) debate with a friend regarding the then new stereo 24 bit/48K audio DVDs coming onto the market. He swore that the sound of the 24 bit "wipes out" the cound of the same program on 16 bit CD. He swore that the difference was "enoumous" and that he could tell instantly which was playing.

I couldn't leave that hanging.

Having a lot of time on my hands, I took the title track from the audiophile re-release of "Kind of Blue" by Miles Davis and imported it into my digital audio workstation (a professional ProTools 24 bit system). Using professional mastering software, I made two additional versions of the track; one bounced to disc as 12 bits (the lower 4 bits set to 'zero') and one bounced to disc as 8 bits (the lower 8 bits set to 'zero'). Simultaneously, I applied noise shaped dither to both versions at their respective bit depths: there is _no_ information below the 12 or 8 bit level on those versions. (Noise shaped dither is less audible than straight dither, and linearizes the least significant bits better). I then took the original 16 bit version and the 12 and 8 bit versions and laid them on my workstation's screen, and sliced them into sections. I took the different bit depth sections at random and edited them into a continuous file at 16 bits so that it could be burned to CD, noting the time where the switching from 16 to 12 to 8 bits occured relative to the display on a CD player, then burned the result back onto CD.

Hey, if 24 bits 'wipes out' 16 bits, then hearing the difference between 16 bits and 12bits or _8 bits_ (!) ought to be like shooting fish in a barrel, right?

So I gave him the CD and he said.........(-:

Anyway, if anyone wants to have some fun, I'll make five of copies of this CD and pop them off in the mail to anyone interested, with the provision that they in turn send it along to anyone else interested, after listening and posting your impressions here. You can also feel free to rip a copy of the CD before passing it along.

Of course, I am not going to reveal right now the timings of the changes....but I will, in due time (-:

Any takers?

PS: You can give me your address by Email so you don't have to post it here.


[This message has been edited by soundhound (edited October 10, 2002).]

Sure write me at rbessinger@deloitte.com and I will give you my address. I think this is an interesting experiment.

I'm in! Email Address: Dollar2@attglobal.net. or maybe you should post your address here and we can send you our mailing addresses. I look forward to it.

charlie@bgtree.com

That does sound pretty intriguing -- I'm at gonk@prillaman.net . If it's a single track (and not too big), I might even be able to scrounge up space to host the WAV file.

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gonk -- Saloon Links | Pre/Pro Comparison Chart | 950 Review

I'll give it a shot.

brianca@ud.com

brianca..

OK, Brianca makes five people, and I have 5 CDs. I'd love to make more, but I've got to feed my cats too!! I've instructed these five people to forward the CD on to anybody else, via this forum after they listen or make a copy. Sorry to have the rest of you wait, but us Outlaws are used to waiting, aren't we (-:

Maybe Gonk can host the file??


[This message has been edited by soundhound (edited October 09, 2002).]

- practice makes perfect?

I'll see what I can do about hosting the file, at least for a couple weeks.

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gonk -- Saloon Links | Pre/Pro Comparison Chart | 950 Review

By the way, for those of you getting the CD - I'll give you a hint: The song, "So What" starts out in 16 bits, unaltered, and then goes to ?????

Also, I might have been unclear, using the word 'truncated' for making the 12 and 8 bit files. Actually, the software takes the least significant bits of the original file, and 'folds them into' the least significant bits of the new file, during a digital bounce to disc, while adding the noise shaped dither.

[This message has been edited by soundhound (edited October 10, 2002).]

I can't stand the suspense... was your friend able to tell the difference? Perhaps not accurately, but at least that a change occurred?

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Matthew J. Hill
matt@idsi.net