This is absolutely the same behaviour I have been observing for some time now. Disks burned on my yamaha drive at higher speeds have a very 'fizzy' sound particularly noticeable during louder passages - like the audio file has been run through an aural exciter with all nthe knobs set to 11. I know that the WAV file is OK, I can play it back through the optical interface on my PC straight into a digital mixer and then out to a variety of speakers. No problem. There is definitely a clearly audible difference when CDs are burned using different write speeds. The difference shows up more on my Car CD player and Pioneer personal Hi Fi than it does on the Denon CD player connected to my domestic Hi Fi. My presumption is that the difference in audio quality is due to the player(s) heavily error-correcting during playback, so the different error rates MUST be being caused by the different burn speeds. I wish there was a simple way of measuring the error rates on different disks. Richard
Mr lemon, The laser scattering is a marketing mantra which was used when the black CD-R was introduced. But the black material can't absorb laser wavelenghts, since the disc wouldn't work at all if that was the case (or it would significantly reduce reflectivity). I personally think its a hype, but there are some very high quality black media labels on the market, so they are not a bad buy. A debate isn't my goal either. I would love to see an issue like this nailed down with solid proof to back it up. I haven't seen such thing online yet. Ok, if the difference is strongly audioble, as you both describe the treble etc., then it should be visible in some sort of frequency analysis too? Now the only problem is to get the information loss-less from the CD player. Can either of you use a digital output of the CD and record tracks back to PC for analysis?
Rip your original and your copies into wav files, and use EAC to perform a compare wav between the two files. It must only show an offset difference (repeated/missing samples a the very end). Any "different samples" somewhere inside the file is data corruption and means that either the copy was not ripped properly, either it was not burned properly. In the case of error free copies sounding different, so far, there is no explanation, it should be impossible, unless the player is bad and can't read the copy error free. It can be checked from the SPDIF output, if you have a soundcard capable of setting its clock in slave mode on the digital input in order to record the digital stream without performing ASRC between the player and the card clocks. Then you can compare the recording with a rip and see if there are differences (it won't tell if the errors are in the rip or in the copy, but it is easy to get an error free rip with EAC's "test and copy" method). There is no evidence of the fact either. There has never been any objective report of this behaviour at all, neither from measuring instruments (distortion, frequency response...) nor from anyone's ears (positive blind ABX test, that would be an objective result).
Correction : there is an explanation. Bob Katz (http://www.digido.com , jitter) thinks that the pit/land jitter embedded into the copy burdens the servo engine that is spinnig the CD, that in turn burdens the power supply, that in turn unstabilize the onboard oscillator, that can't guarantee an optimal D-A conversion. But it's not been measured, it is just an hypothesis.
Hi, I made a few TEST Cd's. I used Original music that was recorded by me, mixed to DAT, transfered to PC via S/PDIF and saved as WAV files. I made two copies. First at 1x and the second at 8x. I Ripped the files back to the hard drive and did the compare to the original WAV File. Both 1x and 8x rips had the SAME errors, which are the missing samples mentions in Pio2001's message, and both are 0:00:00.0012 Longer then the original. I also burned the wav as DATA, but the data disc file compare had NO errors at all. Data copys seem to be perfect, its when one does Audio copies that the above errors appear. Im at a loss as to why it sounds different. I have read a lot on the Jitter argument, and it does sound like a good one. Usually pit/land jitter does not effect the bit compare, but does cause audible differences. The argument is that the CD player laser does need to work harder to read the pits/lands. After all, CD's are really an analog media, with digital info on them. The laser is measuring the length of pits for its count of 1's (or 0's I forget which). TOM...
Surely ripping them using the drive you recorded them on isn't going to prove much? My problems with audio quality only show up on other playback systems (my car CD player, personal hi fi). Same WAV file. Change the record speed, it changes the audio quality on those players. The disks will read fine on the burner, and play fine on my domestic hi fi. I'm convinced that the car and portable hi fi can't cope with the error rate, and that changing the burn speed is changing the error rate. I just don't have a way of measuring it. Richard
Hi Richard, I ripped them using a completly different computer with a Pioneer DVD-Rom and LG Burner. I didn't use the Yamaha 8424S for the rips. Stil, i am in total agreement with u about the sound quality issues. Burn Speed does change quality, but my new LG 40x burner does not really show much quality drop with burn speed. The LG 8400b's lowest burn speed is 8x. I notice a slight difference between this burn and the original, BUT if i burn at 24x, its the same difference. Both the 8x and 24x burns sound the same. Also, no matter wat speed i burn on the LG, it sounds better then the Yamaha burner ever did. I can only guess that CD-R drive technology has improved quite a lot since I bought the Yamaha 8424s. I think a newer CD-R with more burn options (like speed below 8x) will make ur burns much better. Now I'd like to know which CD-R drives are best for making good audio dubs? I wonder if there is a difference from one CD-R drive to another? TOM...
mr lemon, Do you experience the quality difference with any CD audio player, or just one? Quality differences between CD-R drives: There is no such information available as nobody has documented audio quality differences. I would look at the audio player, not the CD-R drive.
Mr_Lemon wrote : "I think a newer CD-R with more burn options (like speed below 8x) will make ur burns much better. " That's not sure, there are more and more reports of bad burns at low speed : http://forums.afterdawn.com/thread_view.cfm/15634 http://www.cdrinfo.com/Sections/Articles/Specific.asp?ArticleHeadline=Jitter+Tests&index=4 http://www.cdrlabs.com/phpBB/viewtopic.php?t=8854 EDIT : Oops ! I'm linking this very thread, ha! ha!
I can't explain why would 8x burn come out worst than 16x or 24x ones, but at very low speeds (1x and 2x) we have to keep in mind that the laser will be at writing power for 83 or 43 minutes, and the heat build-up, both on the disc and on the laser, could possibly cause added jitter???
Hi, The quality difference occurs with ANY CD Player. While it is harder to hear on boom boxes and car decks, it is still audible. Most of the CD players and play back systems I have access too are pretty high fidelity. The Boombox being the only low fidelity cd playback that tends to hide the differences, mostly because they have 'boom' built right in, no matter wat ur listening too. TOM...
[rgoodwin] I've produced unreadable audio disk with TEAC 40/12/40 drive at 4x which (older TEAC drives, i.e. my previous 16/10/40) regulary achieve high quality audio records. Before weeks ago I've tried something interesting for me: I've used low quality disk and burn audio CD using LiteOn 48/24/48 at 32x and quality was pretty good! That was unexpected suprise for me. Then I've tried at 4x and the quality was the same... At 4x LiteOn use CLV and CAV at 32x.. but no one of these methods produce gabs. I believe that recording media is also extramly important. For example LiteOn recomends: RICOH, RITEK, PRINCO etc..(http://www.liteonit.com/english/english-s-faq-cdrw.htm) moreover writing method is also important, so not always you can rely to low writing speeds (TEAC case). I guess that CAV is better than CLV (I talk about quality, not about max. possible write speed)? Anyway, today's CD-RW are really perfect and they could burn audio CDs with the apprx. same quality at 4x and 32x respectively! Any one to confirm my experience?
Just to clarify things: If someone goes on and reads the 'Saga of black CD-R', keep in mind the the author seems to have quite little idea what he has been writing about.
