I'm not dreaming - these are great CD copies
I’m not dreaming - these are great CD copiesI think your hear an extra something to you good or bad) that error correct gives. Original retail is always best. There’s a lot more laser error correction goes on in a burnt cd compared to a stamped retail CD see the "pits" the laser has to read. Left moulded/stamped retail CD pits Middle and right burnt CD-R pits one gold one normal silver https://www.iasa-web.org/sites/default/files/tc05-fig20.jpg Cheers George |
A lot of CD copies do sound better than the original CD. I think it has to do with error correction. Watch a CD spin in a top loader with a window. CDs are not perfectly balanced and will oscillate. I believe this can cause read errors. I think some burned CDR copies are easier to read and need less error correction. I am sure some CD players have more trouble than others. CDR blanks made in Japan are the best. Taiyo Yuden are excellent. But not all Fuji are Taiyo Yuden. Look for made in Japan on the package. I know that a number of years ago, you could pick up 50 CD spindles of made in Japan Fuji for a few bucks just about everywhere. I think they may have been closing them out. The Blanks made in China are the worst. Cheap blanks can deteriorate over time and become unreadable. Heat and sun light can also coause deterioration. Software, speed and type of burner can also have an affect. I still have a Plextor Premium CD only burner in my compuer. This is all basic stuff that every old Grateful Dead fan knows. |
A lot of CD copies do sound better than the original CD. I think it has to do with error correction. Watch a CD spin in a top loader with a window. CDs are not perfectly balanced and will oscillate. I believe this can cause read errors." I believe this can cause read errors." And play/write/replay errors Think about what you said, the errors are still there if you burn them, even more so as then there are two reads and a write with errors from all three. What I posted is correct in my last post, re the pits and the burning v stamped/moulded, there is more errors in the burnt than the stamped/moulded original retail cd, I've checked this with an error counter in a Genisis Digital Time Lens that can give error figure count Cheers George |
nonoise There is a review (that I can’t locate) that explained how a laser reads the physical pits and grooves of a CD. It’s being done in an analog fashion ( a mechanical process) which then had to be processed into the digital domain. >>>Exactly! The pits and lands are non reflective and reflective areas, respectively on the metal layer. The geometry of the pits and lands and laser assembly is such that when the CD laser beam hits a pit the reflection is canceled due to wave interference so the photodetector detects no signal. The photodetector only detects reflected signal from lands. The length of both pits and lands varies and it’s the series of various lengths of pits and lands that determines the digital information in the analog to digital converter. Diagram 1 - CD Laser Reads Bumps (Pits Inverted) and Lands, both of which have reflective metal surfaces. The photodetector receives no signal from bumps, only from lands, due to destructive interference of light waves. See last paragraph below. Pits and Lands come in 9 different lengths, from T3 to T11. T3 = 10001 T4 = 100001 T5 = 1000001 T6 = 10000001 T7 = 100000001 T8 = 1000000001 T9 = 10000000001 T10 = 100000000001 T11 = 1000000000001 since the spiral of pits and lands is Nano scale any vibration or wobble of the CD can force the servo mechanism to go into oscillation, producing read errors. Also the background scattered laser light gets into the photodetector, producing errors. Thus painting the outer edge of the CD Green prior to ripping will produce a better rip. |
