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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
monroemed
21 posts
 
Gents, For burning copies i have always found the computer route to be substandard despite your read/copy speed. I use a dual bay HK for doing my copies. Sure the real time transfer is better than the 4X transfer, but I've found some recordings are more unforgiving than others. This seems to be independent of the original recording quality. When it comes down to it...you are on Audiogon. Therefore you probably have decent( i.e high cost ) components. Face it..copying CD's is piracy. Not that I'm entirely opposed to this! You gotta face the facts... the originals are better than the copies! If you are someone that calls themself an audiophile or enthuasiast just suck it up and pay the cd prices. Even HDCD's aren't that much...so quite whining :) YOU GET WHAT YOU PAY FOR!!!!!! Later! Hunter
garfish
1,840 posts
 
Hi Hunter; When I first got my Pioneer W739 CD recorder, I was convinced that CD copies actually sounded BETTER than originals (actually different, and a sound I liked), but I am willing to back off that original assessment and now say that the copies sound just as good. The main reason I got a CD-R was to make compilation CDs. I have made a set of four CD-Rs that I call "Blues and Soul, Nice and Slow". This set was made from 50-60 different CDs chosen from my blues and soul collection of about 250-300 CDs. To select the songs, determine recording levels and do a perfect job of recording these songs on 4 CD-Rs took me weeks. I have 15-17 songs on each CD for a total of 70+ minutes of music per CD, or 280 minutes of MY FAVORITE blues and soul songs. My point: I bought all of the original CDs and recorded them on the (more expensive) consumer audio/music CDs, and I do not consider this "stealing", in fact I created something musical that didn't exist before, and I would place a value on each of these CDs of around $100.-- to me. These compilations do not exist anywhere else in the world, and IMO this is the real value of CD-Rs. I have done other compilations but nothing approaching the complexity of these blues CDs. I occasionally "burn" a copy for use somewhere else or for my daughter-- something she wouldn't buy any way. CD-Rs really are effectively no different than cassette recorders, which I also have. I am not, and refuse to "whine" about this. Respectfully. Craig.
monroemed
21 posts
 
Craig, I see your point, it's well taken! They are great for the purpose you spoke of, I too use them for this. Possibly as the technology advances (which probaly won't be in the too distant future) cd recorders will be able to make exact copies. But for now I'm afraid it's not so. Take care! Hunter
1439bhr
85 posts
 
Here's what's puzzling me... doesn't a CD-ROM burner have PERFECT bit-for-bit error-free capability when recording a computer data or program file? Think about it: if perfect (i.e., vanishingly small error rate) transcription and playback aren't achieved, recordable CD-ROMs wouldn't be acceptable as a reliable media for computers. Lesser performance for audio CDs and componentry is not acceptable, as low cost equipment can achieve virtual perfection relative to the writing and reading of digital data on optical media, as demonstrated by the personal computer industry.
richlp2523
1 posts
 
Wow...very interesting! Could be increased "jitter" in the copies. The quality of the circuitry in the signal chain leading up to the machine used in a manufacturing enviornment certainly must be better considering the cost of the equipment and the requirement for a minimum of inconsistency in that setting. I recently had two copies of a very hi-fi CD that is out of print made, one on a PC and the other with a Phillips stand-alone copier. I haven't compared the two disks critically, but each has at least quite acceptable sound quality from what I did hear of them, although the PC made one seems to have the horn section (The music is Swing/Jazz and Western Swing, VERY well recorded, produced & mastered) a bit more "out front" compared to my recall of the original factory CD. I have to sit down and really compare these two CD copies!
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