mccamy@squirt.DEC (07/30/85)
From: "...decvax!decwrl!rhea!Squirt!McCamy" Merrimack, New Hampshire Is there really any significant differences in sound quality between the lower priced and higher priced CD players? If so, who makes the best CD player for the money? Does anyone have any experience with the Carver CD Player?
karn@petrus.UUCP (Phil R. Karn) (08/02/85)
> Is there really any significant differences in sound quality between the lower > priced and higher priced CD players? If so, who makes the best CD player for > the money? Despite those who claim all sorts of audible differences between CD players, a fairly carefully controlled test conducted recently by several net.audio members (ulysses!smb, hound!rfg, rabbit!jj and myself, among others) revealed that none of us could discern ANY differences WHATSOEVER between the CD players tested. In blind A/B testing in which carefully synchronized players played identical discs with matched signal levels, none of us was able to do better than chance at telling which player was on at the moment. The test included players of widely varying prices, both with digital and analog reconstruction filters. The results were not unexpected, considering the almost ruler-flat frequency response characteristic of virtually all CD players. In summary, I wouldn't waste my time comparing the sound quality of different CD players. You should instead shop for price, reliability, programming features, error correction capability, etc. Phil
5121cdd@houxm.UUCP (C.DORY) (08/02/85)
<chomp> There you go again Phil -- applying good ol' transitive property No. 33 again: "If I can't hear it on my equipment then it doesn't exist". I will have to admit that many of the differences that do exist are not nearly as great as some of the underground audiophobe magazines would lead you to believe. However, I have heard differences in CD players on my equipment, with my ears, also in carefully controlled tests. As well, I have had several opportunities to compare master recordings with the production CD -- this is VERY interesting. But, since a documented test has been performed with the utmost of care (i.e., the best possible gear and unimpeacable recordings), performed by the most worldly scientists with unquestioned experience in audio (and of course, with no preconceived bias), I guess my observations aren't worth &%$#. I guess from your conclusions, Phil, the CD player we should all run out to get is the Sears (Craftsman) unit on sale (i.e., reliability, price, etc.). In all seriousness, in order to make claims even approaching what Phil and his crew made about CD players (or any other piece of audio equipment for that matter) one needs to eliminate or, at least, drastically reduce the uncertaintity (e.g., the source material: How was it recorded? What signal processing was used? What equipment was used? Any time-domain correction? And if you believe what you read on the CD jewel box, well...). Also, the equipment under test -- was there a wide enough sample of technology, or were all the units around the same price, same LSI chips, etc. (Remember, Matushita (sp?) is a monster company.) Believe it or not, all of these things, if not properly controlled or noted, would affect the outcome of even the most carefully executed listening test. Once we realize that broad, sweeping conclusions cannot be made from myopic testing, flames like this will no longer be necessary. Craig Dory
smb@ulysses.UUCP (Steven Bellovin) (08/03/85)
> <chomp> > > There you go again Phil -- applying good ol' transitive property No. 33 again: > "If I can't hear it on my equipment then it doesn't exist". I will > have to admit that many of the differences that do exist are not nearly as > great as some of the underground audiophobe magazines would lead you to > believe. However, I have heard differences in CD players on my equipment, > with my ears, also in carefully controlled tests. As well, I have had several > opportunities to compare master recordings with the production CD -- this > is VERY interesting. But, since a documented test has been performed with > the utmost of care (i.e., the best possible gear and unimpeacable recordings), > performed by the most worldly scientists with unquestioned experience in audio > (and of course, with no preconceived bias), I guess my observations aren't > worth &%$#. > > I guess from your conclusions, Phil, the CD player we should all run out to > get is the Sears (Craftsman) unit on sale (i.e., reliability, price, etc.). > > In all seriousness, in order to make claims even approaching what Phil and > his crew made about CD players (or any other piece of audio equipment for > that matter) one needs to eliminate or, at least, drastically reduce > the uncertaintity (e.g., the source material: How was it recorded? What > signal processing was used? What equipment was used? Any time-domain > correction? And if you believe what you read on the CD jewel box, well...). > Also, the equipment under test -- was there a wide enough sample of > technology, or were all the units around the same price, same LSI chips, etc. > (Remember, Matushita (sp?) is a monster company.) Believe it or not, > all of these things, if not properly controlled or noted, would affect the > outcome of even the most carefully executed listening test. Once we > realize that broad, sweeping conclusions cannot be made from myopic > testing, flames like this will no longer be necessary. > > > Craig Dory Craig: all that Phil -- and ark and jj and rfg and mjs and I -- said in our postings was that when we compared players, after controlling as best we could for other influences, we did not hear any difference that was attributable to the CD players with any degree of confidence. We listed, as carefully as we could, the recordings sampled and the equipment used (plus, of course, the number of cats present....). Before our second test, we listed the sound system in advance, in case anyone wanted to tell us that it was hopeless to try it. As I recall, we even invited you to the testing, but you couldn't make it on such short notice. We make no claims that our test was the ultimate, or that we were the ultimate arbiters of sound quality. We do share a belief that much of high-end lore is closer to mythology than science. We did and we do invite you (and everyone else on the list) to conduct similar tests of your own, taking as much care as we did to control for outside influences, such as mismatched output levels. If your test site is within reasonable range of Westfield, NJ, I'd be glad to attend -- as a control subject, if you will. If you want to compare some audiophile player -- say, the Meridian or the Mission -- to another, I'd be happy to co-operate. You can pick the music, the recording, etc., so long as there's a duplicate copy to play simultaneously on another player. Let me summarize my own conclusions from the tests we ran (which were initiated when I started shopping for a CD player). I emphasize that these are my own opinions, not necessarily those of my fellow testers: (a) CD players *do* sound substantially alike, at least among the ones we tested. (b) digital vs. analog filtering made no audible difference. (c) any sonic differences that do exist are far dwarfed by other factors, such as precisely where in the room I (or a cat...) is sitting. (d) given all that, I'd rather spend somewhat less on the player and more on disks -- the goal, after all, is to listen to music, not equipment. (e) despite point (b), I intend to buy a player with digital filtering, because I feel that the precision components used in a good brick wall filter will age and drift during the useful life of the player. Others are welcome to their own conclusions, and to any explanations they wish for why Craig hears something I don't. Maybe my hearing's been ruined by too many years in computer rooms. Maybe my ears aren't educated enough, because I don't own any high-end gear. (I can indeed hear the difference between my speakers and more expensive ones; I simply have a set of spending priorities that don't allow me to indulge.) Maybe my bias -- freely admitted -- prevents me from hearing any differences. Or maybe there is no difference, and Craig's bias is at fault. --Steve Bellovin ulysses!smb P.S. If anyone out there would like to see our postings (again), drop me a note. If there's sufficient interest, I'll repost the articles; otherwise, I'll reply by mail.