CD Copies...why do they sound worse?


I had a theory that I haven't discarded yet that not all CD blanks are equal in terms of composition. Yes, they all are made of aluminum and polycarbonate, and when you burn a CD you are creating small holes, or dents in the blank. There is the red book standard that must be adhered to, but as in anything else, I'm sure there are better grades of aluminum and poly available, you get what you pay for. Since the laser reads the digital stream by optically scanning the surface of the CD and interpreting either a one or zero, you'd think it's a go/no-go operation. The original and copies do not sound the same, even to the uncritical ear. I thought for a while it may have had something to do with the relative quality of the CD blanks I was using to copy, in other words, the pressing plants simply use a better grade of master CD's. My friend has a contact and we were able to acquire bulk CD blanks from Saturn Disc that makes CD's. No difference, copies still aren't right. I guess we can eliminate the CD blanks for now. Here's where things get a little outside normal thinking in my twisted logic: we know there are error detection and correction schemes used in intrepreting the data on the CD, employed when the bit being read isn't immediately recognizable to the player. Is it possible the home-made copy that was burned using a cheap consumer grade burner, contains more errors? Are the pits burnt in the CD either irregular in shape or depth? Does the laser in these consumer grade CD burner introduce errors? If so, the EDAC is pretty busy, and doesn't always get it right, which would explain a general lack of quality due to latency delays in the data stream while the EDAC does it's work, and in the process is bound to mis-interpret zeros and ones, there is no 100% accurate EDAC. To me, this is a good place to start in terms of understanding the obvious differences in sound quality.
jeffloistarca
"How can this possibly confuse you. The sound of the recorded CDR played back on the same CD player sounds better than the sound of the original CD that the CDR was recorded on played on the same CD player". I'm confused! Sounds like gobbledygook to me. But seriously, if the playback machine is the same as the source used for the recording, then scientifically, there cannot be any improvement whatsoever, as any error which is heard during playback of the original CD will also be recorded onto the CDR. In that case the only possibility is that the CDR is the same, or worse; perhaps you prefer the sound even though the bit error rate is higher.
this all depend on the way of the duplication. If we use a straight duplication - how can a digital be different? Most of the PC duplication is combining a compression in the copy - check the file size(from original to the copy file)
Perhaps the process of copying CDs is adding some sort of distortion (deviation from the original) which you find more agreeable than the original. This would support of perceived increaase in quality while also supporting the position that the copies will not be identical in every respect. For now it is the best mechanism available for customizing this recording medium. Frankly, if it sounds better, go for it.
I'm sorry I arrived at this thread late. I will share my exprience. I have owned a Marantz CDR620 for about eight months now. Initally the source was a Wadia 850 and is currently (and will be for a long time a RA CD50) digital IC is from LAT international. Copies in real time. I have been pleasantly surprised with the results. My observations have been that at least the Marantz was sensitive to the CDR type being used with Mitsui providing the best performance (Apogee a close second). The most surprising thing has been comapring the same recordings I made with the 850 to those made with the CD50. Comparing copies of WELL recorded material there is a significant difference that in my opinion mimics much of the differences I notice in general between the 850 and the cd50. I have no explanation for this but can say with honestey that for the most part I prefer the copies I have made of high quality recordings only (particularly Mofi digital) from the cd50 to the originals.This is particularly true of early digital recordings with "emphasis" which can be ignored by the 620. I have no business speculating on this so I will defer. In an interesting review on Soundstage of the Linn CD12 the author comments on a similar observation using the 620. I don't get it.