jbn@glacier.STANFORD.EDU (John B. Nagle) (08/07/88)
I have yet to see a CD player, even at the high end, which displays error rate information. At the very least, I'd like to know whenever error correction was unsuccessful, since the logic tries to interpolate something reasonable in such cases but the result is usually disappointing. But this seems to be something that doesn't get put into players. Given all the blithering from some vendors about how their transport has better bearings and suspension and such, I'd expect to see readouts demonstrating that that was useful. After all, if you're not getting any uncorrectable errors and all the corrections are performed properly, no further improvement in the digital portion of the system is possible. John Nagle
btk@cbnews.ATT.COM (Bryan T. Korff) (08/08/88)
In article <17620@glacier.STANFORD.EDU> jbn@glacier.STANFORD.EDU (John B. Nagle) writes: > > I have yet to see a CD player, even at the high end, which displays >error rate information. At the very least, I'd like to know whenever >error correction was unsuccessful, since the logic tries to interpolate >something reasonable in such cases but the result is usually disappointing. > John Nagle I "read an article" reporting on a CD player that did give some kind of read-out of error correction. The player was on display at one of the Consumer Electronics Shows. The interesting point? The number went UP on subsequent playbacks of the same CD. Maybe that is why you don't see this on home units. "Perfect Sound Forever"
jps@wucs2.UUCP (James Sterbenz) (08/09/88)
In article <17620@glacier.STANFORD.EDU> jbn@glacier.STANFORD.EDU (John B. Nagle) writes: > > I have yet to see a CD player, even at the high end, which displays >error rate information. At the very least, I'd like to know whenever >error correction was unsuccessful, since the logic tries to interpolate >something reasonable in such cases but the result is usually disappointing. I've often thought that this would be a good idea, for several reasons. Since nobody seems to really be SURE what the lifetime of the discs is, and since we've heard about the potential ink bleed-through, it would be nice to know if your extensive collection of CD's is slowly self-destructing. If it was possible to monitor the error rate (especially correctable errors), disks could be copied using a writeable optical drive, BEFORE its too late. -- Teo Computer and Communications Research Center Washington University in St. Louis 314-726-4203 INTERNET: jps@wucs1.wustl.edu UUCP: wucs1!jps@uunet.uu.net
tomp@vsi1.UUCP (Tom Pohorsky ) (08/09/88)
In article <800@cbnews.ATT.COM> btk@cbnews.ATT.COM (Bryan T. Korff) writes: >In article <17620@glacier.STANFORD.EDU> jbn@glacier.STANFORD.EDU (John B. Nagle) writes: >> >> I have yet to see a CD player, even at the high end, which displays >>error rate information. At the very least, I'd like to know whenever >>error correction was unsuccessful, since the logic tries to interpolate >>something reasonable in such cases but the result is usually disappointing. >> John Nagle > >I "read an article" reporting on a CD player that did give some >kind of read-out of error correction. The player was on display >at one of the Consumer Electronics Shows. The interesting point? >The number went UP on subsequent playbacks of the same CD. Maybe >that is why you don't see this on home units. > >"Perfect Sound Forever" To qoute from Stereophile magazine, March '87, p. 31: "I suggested he (Wayne Green, moron and publisher of Digital Audio mag) ask Stan (Curtis, of Cambridge Audio: VERY expensive CD players) to demonstrate, with his machine's error correction readout, the fact that CD's wear out a little with each play - 1's and 0's sliding off the disc into thin air." The author is Sam Tellig. If this is indeed the case, I'm sure anyone/everyone involved in that industry is reluctant to advertise it. "Perf ct Soun Fo ever" :-(