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.
Get a copy of Audio Magazine I think it was Jan or Feb 2000. It explains in detail the answer to your questions.
There was a thread recently, where they thought the copies actually sounded "better". (CDR's don't use aluminum as the substrate, it's a photosensitive chemical layer). I don't think there are any simple answers to your questions! It's definitely not as simple as reading "either ones or zeros", either..........................Peruse The Complete Guide to Highend Audio, familiarize yourself with the finer points, and then e-mail a few high end digital manufacturers for their thoughts on this (but don't ask dumb questions, and don't hound them too much).
Hi Jeff; I'm surprised to see your comments re: poor quality CD copies. I have a Pioneer W739 CD-R and my experience has been just the opposite-- I actually get better quality music on the CD-Rs, eg more crisp, more clear, and more dynamic. The differences are not dramatic, but they are noticeable. There was another thread here on AudiogoN that concurred with my observations, and Ramstl postulated that because the CD-Recorder actually burns the pits into the CD-R blank rather than pressing them, they may have sharper edges that are more easily read by the laser mechanism of the player. I am curious to know what aspects of music are lacking or overdone on your copies, and what kind of CD-Recorder you are using. I've used Maxell and Memorex CD-Rs with excellent results. I'll look up the Audio magazine article you refer to. Craig
Craig, I definitely do not believe that the edges are crisper on a CD-R. You have to understand that a CD-R is made while it's spinning, and CD's are stamped. It would be that the stamped ones have the crisper edges (all things being equal...which they aren't). AND, CD-R's use a photosensitive chemical layer, and the holes are bound to have LESS defined edges than the stamped pits, if anything. There might be other advantages, but seculating about it won't get you anywhere. Talk to some experts, and see what they have to say. And carry a CD-R to one of your friends with an electron MICROSCOPE, and compare it with a stamped CD. I think the holes in the chemical layer are bound to have some "wiggle" around their edges, just as photographic film has a grain...but that alone wouldn't necessarily cause poorer sound quality (these wiggles would be very small, compared to the hole the laser burned), and there are complex issues to consider here, that none of us are qualified to discuss...other than subjective opinion and observation........................Right now, it's just like anything else on here...Whatever you like, do it that way, and be happy. Personally, I have no opinion as to whether a copy sounds better, or worse (the CD-R's I have are copies of originals that I did not own, which is the whole point of CD-R in the first place). I'm just happy with the "tweaks" I do to both CD-R's and CD's, and enjoy both.
In response to those that believe the copies they make sound better, I reply that it is impossible. It is only possible to be as good. How can you possibly make it better? How can you upgrade onto your copy what never existed on the source. Now, with that said, I believe the copy can sound better if it is played back on better equipment. Example: If I record from my Meridian 508.24 to my Nakamichi ZX-9 cassette, I could put that CD into a inferior CD player than my Nak and the cassette will sound better than the CD it was recorded from.
I should have mentioned when I posted this originally, the burner I use is an external Yamaha SCSI burner hooked up to my laptop. This set up is great for a computer, but it's entirely possible that a unit intended for audio use would provide better results. Another guy I know, using a different CD burner, discovered the same disappointment, and he's not an audiophile by any means, but he is an engineer and will likely get to the bottom of this mystery. In any event, there is a very real audible differences between the orginal CD and the copied CD's I've made, I think simply ignoring it and enjoying the music isn't bad advice...Jeff
My guess is that information is lost during the process before it reaches the copy and possibly lost in the process of writing "burning" it.
Jeff, I've made CD-R's on the computer too, and you have to make sure it's not writing them at several times normal speed. I did it at like 30x once, and yes, that sounds terrible, and even a deaf person could hear that difference in a blind test 100 out of 100 times. Did you burn at normal speed?
....I agree Carl; think I'll just enjoy what I have. Cheers, Craig.
Yes, if we could all enjoy what we have, we'd be happier and better off.
Probably because your doing it through a computer. I have had the experience that the CDR always sounds better than the original. It's probably not the kind of diffrence that a pro audio engineer who is standing to the side of a pair of Yamaha NS10s perched atop his 250,000.00 recording console would notice, but I bet if I had a guy like Carl over to hear the diffrence, he would be recording all of his favorite CDs on CDR it's that good. The argument that it can never be better than the original reminds me of the cable is cable argument. My setup is an outboard (not hooked up to a computer) CD recorder using a Illuminations D60 SPDIF cable from a Meridian transport and I get CDR copies that are in every respect better than the original. CDRs in my opinion are more of a pro audio thing than an audiophile thing. The CD recorder I own is something that I found out about through pro audio, not hifi. I discovered for myself that is sounds better. I have never read that CDRs sound better than the original in a pro audio magazine. That is the problem with pro audio, they totally dismiss the hifi thing. It's these kind of opinions that are producing the majority of recorded music that is out there too. To just simply say that is can't sound better because that just doesn't make sense is pretty lame to me, you must be a proffesional recording engineer.
Ejlif, your comments confuse me. First let me say I am definately not in the "a cable is a cable camp"! Without changing the orginal, how are you making it better? I could understand you liking the sound your CDR puts out better than your CD player. Maybe that's where I miss it, CDR's naturally have a better sound, like vinyl sounding better than CD's.
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 know digital is just 1s and 0s how can it sound diffrent, it does and not by a small margin either. I don't know the scientific reasons behind this, but I do know what my ears tell me. This is definately the kind of diffrence you would be able to hear on a player as fantastic as the Meridian 508.24 (good choice)
Ejlif, I only have a second, but I want to clarify something real quick. It appears I may of come off as one of those that think highend is a joke; that couldn't be farther from the truth!!!! ...this is why I own a 508.24. I was one that wasted my time arguing with the yahoo's on about cables, I have heard the difference, heck my wife hears the difference and she could care less!
Vinyl is a totally different medium, and sounds better because there is both more dynamic and more tonal resolution stored in, and passed through the fromat. Not because of the material it's stored on, for example. Let's just keep this on CD-R's, if we could. Ejlif says he doesn't know why a CD-R would afford better performance, that "it just does". If we wanted to know why that were true (if it is) we'd have to ask several of the best designers in the field, and not just speculate about the "why". There are complex issues that would need to be dealt with, about how CD's get read in the first place. You should all read what Harly has to say about CD playback, in the back of TCGTHA.
Here's a case where it's not necessarily so that "bits is bits". It is true that the transcription (CD-R) cannot be more accurate than the original. But even if the transcription is identical to the original, the playback machine may read the original aluminum pitted disk more or less accurately than it reads the dye marks on a CD-R. Compounding that is the likelihood that the CD-R will have transcription errors and that all CD players have built in error correction coding processing that is used to detect and interpolate through, if not correct errors... too bad that CD players don't have a little instrumentation readout to give some idea of the level of BER being experienced. Looking at the BER for a stamped CD vs the CD-R transcription would give some quantitative clues about what's really going on.
I'd just like to see each under an electron microscope, for starters.
I feel so strongly about the improvement in CDRs over the original that I have sent both the original and the duplicate copy to a friend who of all I know is the most involved and educated person in hifi. I will post his findings on this subject when he tells me what he thinks. Carl if you have one of the same CDs that I have I would be interested in sending you one as well to get your opinion on it. Email me and maybe we can figure out a CD we both own
OK, I will. I'd still like to see each under an electron microscope. You could mail me one of those too, heh heh.
There certainly is a big difference in the blank disc tha t you use. I tried most of the "name" brands TDK, Memorex,Sony etc. and they were not good. I went to a pro recording supplier and am now using Apogee gold mastering disc at $2.19 each including jewel case and they are very good and I am pretty picky. You might try them. They are: APOGEE -CD 74 - GUJ. My outlet is in Seattle but the company is located in Calif and they do have a web site. Good Luck. John
To Jmac48 where can the Apogee CDs be purchased from. Thanks, Ryan
Ejlif: Pacific Pro Audio in Seattle, Wa. 1100 Virginia St. Suite # 202 Seattle, Wa 98101 (206)264-9386 Garth is who I deal with. Or go to the apogee web site for a dealer near you' Good Luck, John
Ejlif: I guess I should mention that I'm using a Sony XA7ES (was there flagship until this year) for the source and an Otari CD burner that In purchased from Pacific Pro Audio in Seattle. When I play these back on either the sony or the meridian it is very difficult to tell much difference. When I make an anolog copy (record or tape) the cd copy sometimes sounds better. If you are using a computer to burn with or downloading from the net, I haven't talked with anyone who has had much luck making high quality copies without a huge investment and lots of tinkering.
In my humble opinion the CDR's sound worst because of jitter. The big companies have higher standards then any of the burners. There was a big article in Audiophile about 3 years ago about why the BMG CDs sounded worse then the original company pressings. A detailed comparison was make at the bit level and no differences were detected. Jitter was all that was left. It seems to fit this situation to a T.
Your answer may be found in this article.
"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.
My expereince is that they are always worse.
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.
So I took an Audio CD and a blank, stuck both in a philips dual-deck CD recorder (the consumer kind) and made a copy. Then loaded both disks in my PC and captured 10 copies of the CD image of each disk on to harddisk at high speed. That resulted in 10 significantly different files for each disk. Captured again at single speed (That did take about a day indeed :) and had 10 identical files for the original and 10 identical for the copy, but differences between the original and copy... SCMS!!??!! So I repeated the copy using a machine without SCMS, a stand-alone duplicator I use for software mastering... After the read and compare test, again two groups of 10 images were read at single speed. 10 identical images for the original (Unchanged from the previous set of 10), and 10 identical images for the copy, but the original and copy were significantly different. The final test I did was to write one of the original images back to CD using a CD-R in the computer, at double and single speed. These, again, were read back in the computer 10 times and compared. Both would get groups of consistant readbacks at single speed, but the images were different from eachother and from the original CD. The single speed writes were closer to the original than the double speed writes. So, I burned some more copies at single speed and did the same readback test. All copies were slightly different. All copies were very close to eachother, closer to eachother than to the original CD. Finally, I used a different CD drive to read back the original and the copy... This is where it got interesting. The copies read back binary identical, ie. a copy read on the HP it was written on was identical when read on the HP at single speed and on the companion Mitsumi drive in the same machine. However, the original disk did not work this way! It was consistant on the Mitsumi, and it was consistant on the HP, but the two sets of images differed.... I found that VERY odd!! Anyhow, all in all it resulted in over 60GB of CD images, and actually analysing that much data proofed to be hard, so I did not actually try to correlate the differences. What it proofed to me though is that there is a difference. As to the sound quality of the copies, which is what I was really interested in: The copies made on the PC at more than single speed and in the stand alone duplicator used for software sounded imperfect, clearly audible audio defects like ticks and static. The Philips made copy sounded best, I could not hear a difference. The computer made copy at single speed, to me, sounded almost as good as the original, there were some minor audible differences in the form of static. I used Easy CD Creator Pro to capture CD images and burn CD's on the computer side of things. That was a very long way of saying: No matter what I did, the copies were not identical! That was not what I expected...
Can I throw a wrench into the works? I just copied an HDCD original on my computer and played the copy on my Linn Ikemi (with HDCD decoder). While the player recognized the copy as HDCD (the HDCD light went on), the copy had a lot of unacceptable popping and "static" noise. Any explanations? Any advice?
Gboren1, try making a copy again, this time READ the original and WRITE the copy at single speed if you did not do that the first time. The behavior you describe seems to be normal when copying Audio CD's at high speed on a PC.
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 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 quite whining :) YOU GET WHAT YOU PAY FOR!!!!!! Later! Hunter
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.
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
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.
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!
Ummm... maybe you should deguass those CD's... That aluminum becomes mighty magnetized... btw... jitter is induced in the analog domain, not the digital ... (That's where CD's are copied .. in the digital domain)... In fact, CD audio is comprised of 44,000 16-bit words for each second of sample time. A CD is copied bit for bit and then verified... There is no difference between a copied CD and the original, except for in your mind and possible in your A/D converter during playback. That's the word
Too much noise, not enough jitter immunity on the digital recievers in the cd burners...this all adds up to degridation on the cd copy. Bits are not bits, don't forget the time based errors! These differences can have some of the most detrimental effects on the overall harmonic details of the copied cd. In the end, a "high end" manufacturer will eventually produce a competent sounding abeit expensive cd burner.