Do CD-R's sound the same as originals

Mfgrep - all my experience is with computer CDRs. I used to have one of the Phillips dual-tray copier machines which required the audio media, but I don't still have it to run any kind of comparison test with. There is physically no difference between the two media, just a bit that is set saying this is an audio CD and therefore can be used in an audio CD recorder. Computer CDR drives don't pay any attention to that bit, and computer CDR media doesn't set it. Robba - absolutely understood. There are three "chunks" - reading the media, getting the data to the DAC and then what the DAC does with the data. All my comments have related only to the first chunk. You're correct that jitter is introduced in a different chunk - namely, the second one. Jitter is of the nature you describe - both the sending and the receiving device have to "clock" the data, and if they are out of sync, you can get "lost" or bad data. Since there is no retry logic, the DACs two choices are to play the bad data or throw it away, either of which would cause audible degradation if it happened very often. One solution seen on some high end transport / DAC combos is cabling that forces the two clocks to act as one, thereby eliminating lack of synchronization. This is a better solution if you're limited to "send and pray" transmissions, but there are much better methods by implementing redundancy into the system. There has to be retry capability, or multiple copies of the data sent so that it has to fail on all connections before the data can't be processed. There are a number of strategies that can be employed with a small re-engineering of the interface, and that have been deployed in other communications-related applications. In any case, the main point of parts of this thread is that the first chunk (reading the data) is a "solved" problem, at least when using computer CD drives, and that if a CDR sounds different than the original CD it's either because 1) the copy wasn't "perfect", or 2)some as yet unexplained aspect of current CD transport /player intereactions with CDR media that differs from CD media.

Thanks...great response. Well....my brother (in LA..studio guy..and a reviewer for a high end mag) purchased the Phillips dual tray audio cd burner yesterday. He called me this am from cell phone and sounded like he just had an epiphany! Although he has had trouble with the sound quality from CDR's, he was impressed with the Phillips audio burner component. He claims that it is as close to a perfect duplicate as he has ever heard. He claimed that there is a bit of crisp harshness, that the vocals seem to not lay back behind the speakers as much as before, and lacked a bit of the air that the original had. He concluded that the audio burner was "damn close" to the original and is great for 99% of humanity. He originally planned to keep the Phillips only if it "made sonically perfect copies", however, he is considering keeping the unit because it is, "close enough" given the savings. He also said that the Phillips unit was built like a typical crappy low-fi electronics. He is going to have to send my some copies so that I can hear for myself, but I'm impressed.

Ramstl: Other than occasionally Kevin Halverson, you won't find any experts here...but you knew that already, didn't you?

Mfgrep: So far, I hear exactly the same thing your brother heard, from the CD-R disc that Ejlif made with his Meridian transport/Tascam CD-R machine. I also hear EXACTLY the same thing with the copies I make with my $89 computer CD-RW. I don't know what all the fuss is about. They ARE NOT a truely perfect copy, but of course they suffice (I never said they didn't). That's why I use CD-R's, and am happy with them. THEY SUFFICE, AND THEY NEED NOT BE UNIQUIVACALLY PERFECT TO SERVE THEIR PURPOSE...................To all the doubters, there's ZERO point in arguing WHY they "REALLY ARE" a "perfect" copy, because those of us who have a decent system, trust our ears (and can hear 20 kHz), KNOW what we hear....DAD-GUMMIT!!! There's no need to waste your time here anymore, YOU CAN'T TELL US THAT WE DO NOT HEAR, WHAT WE (and anyone else who listens, in my system's case) DO IN FACT HEAR!...........Isn't it all really about the music anyway? I thought it was. Apparently you guys have never heard that expression before...

I'm not sure anyone else feels like any fuss is being made - this seems to be a conversation amongst several people interested in understanding what the results and effects of CD copying are and, more importantly, what the critical aspects of the process are for getting "acceptable" performance. I don't think anyone has tried to convince anyone else of what they're hearing for quite a while in this thread. I'm certainly not trying to convince anyone here that they're not hearing what they claim. In fact, I absolutely believe everyone who says they hear degradation. I'm interested in hearing about the types of degradation they're hearing so I can go back and listen more specifically for myself. What I'm really interested in is in trying to understand why they're hearing degradation. It's possible that it's fixable immediately, and it's also possible that, while it may not be immediately fixable, we'll collectively understand what it is we're waiting for that will fix the problem. In the meantime, it seems that one thing that is indisputable is that it is possible to make bit-perfect copies of CDs to CDRs, and yet you keep saying they're not. I'm having trouble understanding what you're basing that on - If I can read and write 650MBytes of data and calculate a checksum across them all and do this over and over and over and repeatedly get the same checksum which has, literally, one in many billions of a chance of matching without the data being exactly the same, and since I do it over and over and over and get the same answer, and the odds of that are therefore billions to the N power - at what point does it become illogical to argue that they're not "truly perfect"? They're not truly perfect from CD to CDR because the way the bits are physically stored is different, but from an information standpoint they're identical. To state that there are no "perfect" copies in the face of these odds doesn't seem to do anything but attempt to cloud the discussion indefinitely, and it would be much more interesting to discuss what is making the CDR copies sound different to those who are experiencing the degraded sound. -Kirk