Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: notesfiles Path: utzoo!watmath!clyde!burl!ulysses!allegra!bellcore!decvax!tektronix!hplabs!hp-pcd!hpfcmp!rjn From: rjn@hpfcmp.UUCP (rjn) Newsgroups: net.audio Subject: CD Reflections Message-ID: <15100001@hpfcmp.UUCP> Date: Wed, 2-Jan-85 03:07:00 EST Article-I.D.: hpfcmp.15100001 Posted: Wed Jan 2 03:07:00 1985 Date-Received: Sun, 13-Jan-85 07:35:24 EST Lines: 99 Nf-ID: #N:hpfcmp:15100001:000:5082 Nf-From: hpfcmp!rjn Jan 2 00:07:00 1985 [] re: observations of a new CD owner (fairly long: ~100 lines) I recently purchased a CD player (Sony CDP610ES), 20 discs and thought I might share my initial impressions with you. Prior to this purchase, most of my listening consisted of FM and some 1/4-in. tapes made from LPs. Although I have an extensive LP collection, I don't play them very often, due to the hassles, not the least of which is having to endure the LP ritual every 20 min. or so. ====================== The PLUSES of CD listening ====================== NOISE: There is no rumble, clicks and pops; no hiss if the CD was digitally mastered; no pre-groove echo or print-thru. DISTORTIONS: There is no wow or flutter if digitally mastered; no compression 'breathing'; no warp wow; no inner-groove distortion. It used to very much annoy me when I found that the producer had put my favorite selection on the last cut of the side - a non-issue with CD. There is also no tracing distortion on loud passages (I don't have a $500 cartridge). WEAR: No worry about the CD wearing out eventually. No need to wait 24 hours before replaying (to allow the groove walls to recover). No worry about stylus wear. The first time you listen to an LP, you know "this is as good as this disc will ever be"; with a CD "it will always be this good". CLEANING: I suppose CDs eventually require some cleaning, but nothing like the discwasher/zerostat (or worse) ceremony LPs require. CONVENIENCE: I now change discs once per HOUR and can use a remote control to skip around and program the disc, not to mention being able to answer the phone without running over to the turntable first. CDs are also portable. Using a "Discman" type portable player is not inconceivable. TAPING: If I decide to make some tapes from my CDs, it will be far easier than with LPs. Cueing is trivial and I can prevue the entire cut to determine the optimum record level, with no wear worries. PACKAGING: I don't have to stock special anti-static record sleeves to replace the LP's paper ones many LP makers use. HANDLING: Although I intend to be as careful with my CDs as I have been with my LPs (some of which are 20 years old), I have far less paranoia about the inevitable little mishaps. ==================== The MINUSES of CD listening ======================= ENVIRONMENT - CDs have pointed out to me just how noisy refrigerators, forced hot air and home computers are. I may have to 'upgrade' my residence :-) EXPEN$E - Yes CDs are costly today. I expect that they will come down to LP prices within two years. Even at today's prices, I'm not complaining. If anyone offered a "lifetime" LP, I would pay the CD price for it. PHASE SHIFT - If the 11 uSec delay represented by multiplexing two signals (each at 44KHz) is not present in the ENTIRE record/playback chain, it may be an issue. I recently read a source which claimed that this is at the threshold of human phase detection. Of course, this would only be perceptible on earphones, since speaker placement distance variation easily exceeds 11 uSec. I haven't done enough headphone listening to know if I can hear any phase effects. HIGH END FIDELITY - If we assume (and perhaps we shouldn't) that all we need to capture are complex signals composed entirely of symetrical sine waves whose highest overtone is 20KHz, a (2x) digitizing rate in the vicinity of 40KHz just won't do. For example, suppose we digitize a pure 20KHz signal at 40KHz, and happen to capture only the zero-crossings. How much information does that get us? We need at least 3x digitizing (60 KHz) to reconstruct a pure sine wave, and I suspect that actual music demands that we use at least 4x (80 KHz). Although my hearing is no longer good enough to have any complaints about CD sound, some of you golden ears are evidently hearing SOMETHING. Keep complaining; it should be possible to develop a fully compatible 88 KHz (or better) CD that would play at 44KHz on existing equipment and at a higher rate on a newer generation machine (one simple way would be to put the alternate samples on the other side, read by a second laser and digitally sync'd). ========================== The bottom line ============================= * I can finally listen (at home) to the MUSIC and not the MEDIUM. * The CD system has the lowest hassle coefficient in audio. * For a first implementation of a new consumer music technology, CD is a remarkable technical compromise. The first music cassettes and 4/8-track cartridges were a step backward. CDs are far superior to all other mass-produced media (I don't consider DBX disc/tapes and PCM tapes to be mass-produced). CDs are probably on a par with audiophile LPs (all things considered) and have superior ease of use. Bob Niland [hplabs!]hpfcla!rjn Hewlett-Packard Ft. Collins CO