Yes, that phenomenon has been reported by many people, and is readily explainable IMO. See this thread and this one. Regards, -- Al |
I experience it all the time.
Look up past discussions.
Buy the best media you can and burn at the slowest speed available. Try not to handle the media with your bare hands. (cotton gloves or a micro-fiber cloth are what I use.) |
Pretty sure it's a PWB thing. A copy always sounds better, even if the CD-R is not a black CD-R.
Pop quiz - Does a copy of the copy sound even better? The second CD-R doesn't know the bits are from a copy. Answer at 11.
Al, what's your readily explainable explanation? Just curious. |
Al, what's your readily explainable explanation? Just curious. Hi Geoff, There's lots of discussion of that in the threads I linked to above, but I think that a good summary is contained in the following post I made in one of them, in which I quoted some of our particularly knowlegeable members: 10-24-11: Almarg
It does seem to me to be technically plausible that many of these reports could be true (and I would certainly expect Learsfool's perceptions to be accurate), although I would expect the magnitude and character of the differences to be highly dependent on the design of the particular player that is being used (and probably also on the particular media, burner, and burn speed that are used).
From this paper by Steve Nugent of Empirical Audio:
3. Jitter from the pits on a CD:
These are the pits in the CD media that represent the recorded data. Variation in the spacing of these pits result in jitter when reading the data. Commercial CD's created from a glass-master generally have more variation in the locations of the pits than a CD-R written at 1X speed on a good CD-R writer. Even though most modern CD players have buffering of the data to create some tolerance to this jitter, there is usually a PLL (Phase-locked-loop) involved, which is still somewhat susceptible to jitter. To determine if your player is susceptible, it is a simple experiment to re-write or "clone" a CD and then listen for playback differences from the commercial version. For newer players that completely buffer the data at high-speed from a CDROM reader to a memory buffer, this jitter is not an issue.
And some excerpts from this thread:
07-19-11: Shadorne
If a disc wobbles while it spins then this may cause cyclical adjustments to the pick up laser servo and these repetitive draws on power may induce variations in the clock through the power supply.
07-20-11: Kirkus
CD players, transports, and DACs are a menagerie of true mixed-signal design problems, and there are a lot of different noises sources living in close proximity with suceptible circuit nodes. One oft-overlooked source is crosstalk from the disc servomechanism into other parts of the machine . . . analog circuitry, S/PDIF transmitters, PLL clock, etc., which can be dependent on the condition of the disc.... One would be suprised at some of the nasty things that sometimes come up out of the noise floor when the focus and tracking servos suddenly have to work really hard to read the disc. Also, while I would expect it to generally be a less significant factor than the noise and jitter issues described above, in the case of discs that may have significant scratches or other imperfections, real-time playback in a conventional (non-memory type) CD player may result at times in error interpolation that is not bit perfect. While if that same disc is read by a computer for copying purposes the computer will be able to make multiple attempts to read any data in which errors are detected. Regards, -- Al |
