Why burnt cds play but not there

[Tristan]

First of all big thanks to every one who helped out on my other thread about getting aburner. I've got one now and am churning out cds but the problem is i got two cdrs with it and burnt tunes onto them and they work excellently on my good sony stereo but not on an older stereo or my ps2.

I bought another different packet of blank cds and after burining onto them, they work on my ps2 and older stereo but not on my good sony stereo????

:? :? :? :? :?

[plastikau]

I can play several types of burnt cd's on my PS2 & stereo no problem, maybe they're old cd's

[Tax Invoice]

If you burn to "Audio CDr" as opposed to general purpose CDR's you will find they play fine, as well as not doing any damage to your CD player. Also when burning audio, burn as slow as possible (pref 1x, 2x, 4x).

[Sean]

actually there is no physical difference between "music" cdr's and regular ones. the difference has something to do with artist royalties and trust funds that they cost more. however that said audio cdr's are normally at the higher end of the quality spectrum. you want to buy a good brand, and some burners used to like other brands more then others, im not sure how relevant that is with todays technology, however external/laptop burners are usually one generation behind. you want a cyanine or azo dyed disc. cyanine is a blue dye and on gold media it looks green, and on silver media it's blue. azo is similar but is a much darker dye. as general rule of thumb the less transperant the disc the better. ive always had good results with kodak, and emtec, probably the best results ive had are with tdk's. another thing to consider is that some players dont like 80 minute cdr's. so try using 74's and see how that goes.

as for the burn speed issue, normally its not too relevant, but seeing as you're on a laptop you may want to step the burn speed back one from the speed you're currently using. this is because depending on your method of connection, the drive may not be able to get fed the data it requires in the time it requires it. burning at 1x 2x 4x is a bit redundant these days coz newer burners are very good, but i dont normally burn at max speed, 75-80% speed is a way to ensure problem free burns.

[digitalboy2020]

It's strange but i've seen this phenomenon before. It seems like maybe the higher end CD players have a finer tolerance and therefore sometimes wont play certain burt Cd's.

[phunkdust]

tax invoice, sorry, but you're full of it :lol:

as sean said, get the right cds... greens or blues are the most sensitive... I use TDK CD-Rs on my sony burner at 10x and I have never had a problem on any cd player i've ever come across...

I assume what with the advice from the ITM crew you got a good burner, so its most likely the media...

[kaossproject]

I use an old Creative burner (1 year old now) and burn on TDK's and haven't found a problem....ever.

So I can't help you as I have never had to solve this problem??

[nicko]

there is actually a reason for that, phunkdust..

The reason why you should burn at 2X max is to allow plenty of time to decode (/decompress?) an mp3.

Apparently. (according to Tom's Hardware guide)

[polarbear]

> as well as not doing any damage to your CD player.

that's a little misleading.....I fail to see how any sort of CD could harm a CD player - considering there's no physical connection between the CD and the diode, and that things generally don't get damaged by unexpected data streams.

IF you have a mixed-mode (AUDIO + ISO9660) in pacific multimedia's format that puts the ROM data on track one of the CD you may damage your speakers if you play track one - but you'd have to play it loud and have a good amplifier. most domestic amps' won't reproduce DC.

as for old vs new. I have a VERY old cd player - no oversampling, bad error correction, bad filters. it'll play anything. perfect for those 'unplayable' cd burns.

[kaossproject]

To avoid the decoding problem you should produce an "image" before you send the data to the burner. Much more reliable.!?

[phunkdust]

nicko - you should always decode to WAV prior to burning anyway - places less strain on your system...

[nicko]

my system is in training. the target - Athens 2004. Strain is a pre-requisite! :)

[Tristan]

cheers guys, i'll go and grab some tdk blue or green ones and see how that goes

[Tax Invoice]

Originally posted by polarbear
> as well as not doing any damage to your CD player.

that's a little misleading.....I fail to see how any sort of CD could harm a CD player - considering there's no physical connection between the CD and the diode, and that things generally don't get damaged by unexpected data streams.



I beg to differ :p
There are some cheaper CDR's which aren't centred correctly &/or off balance due to unequal distribution of protective lacquer, which can do some serious damage to early model CD units. If you can hear a disc rattle as it spins, get it out quick!

When I was a function Dj (yeah, I know, I know), the earlier Denon CD units fell victim all the time.

Yes, you are correct Sean, the 'Audio' branded CD's are the same as high end CDR's (without the royalty fee), but hey, it's a generally a good guarantee they'll work.

I'm experimenting with higher burn speeds with good results also, so I stand corrected there! ;)

[Tristan]

is it possible my good sony stereo just doesnt recognise that brand of cdr. I went into the top audio store in hobart just then and the cdr which doesnt work on the sony stereo works perfectly on the best cd players they've got.

[phunkdust]

hrm, i've got a 15 year old sony component cd player and it plays burnt cds fine...

[Sean]

yeah some cd players dont like cdr's my aiwa compinent stereo doesnt like them. then all my other players do. but my friends expensive yamaha doesnt like 80's

[nicko]

Originally posted by Tax Invoice


I beg to differ :p
There are some cheaper CDR's which aren't centred correctly &/or off balance due to unequal distribution of protective lacquer, which can do some serious damage to early model CD units. If you can hear a disc rattle as it spins, get it out quick!
;)

I heard that in the early days of high-speed cd drives some cheap discs actually broke apart at high rpm...

And on the topic of rotational unbalance, i got some dvds from blockbuster the other night. When i played them they made a noticeable whirring noise in the drive - i took them out to find that some idiot had stuck a barcode on one side.
And to think i put that trash in my new dvd player too! :)

[phunkdust]

thats interesting... rental dvd's are supposed to have special circular barcodes that sit on the inner leader (the plastic around the hole) to prevent imbalances

interesting about the breaking apart discs tho... I've heard a similar story, where by CD-ROM speed is limited to a maximum of about 52x, because at speeds above that the disc starts to warp from the centripetal forces...

[djbc]

Yeah.. TDK are good... we used to use those... we use Sony now (Kmart sell 'em in towers of 50 pretty cheap) & they have no probs.
We've had some similar probs in the past with CD's we've home made behaving inconsistently. The 1x thing can make a difference but that seems to depend on the combination of System/Burner/Media - so a little different for everyone.
I will ad this tho'. As soon as you go faster than 1x you start to loose just a little presence / brightness in the top end. We've done endless tests & A/B sessions with this and it's definitely true... even the most "uneducated ears" could pick the difference.

We tend to follow whatever trend 301 use when making master discs, they currently use the Sony 74min CD-Rs (last I checked anyway) and they always burn the master disc in real time. So if it's got to be the best possible sonically, then go real time.
;)

[driload]

this day and age there isnt much difference between the mid-price cd-rs by known brands

TDK have never failed me nor any Metal Azo dyed brand (acer comes to mind)

of all my cd burners the two i use most are older then 2 years, the one in my main machine is about 4 years old

yes never burn an IMPORTANT cd-r faster then 1X

the reason for this is technical and more cautionary then anything else.... basically although a cd-r with audio is Digital (of course), the way the data is created can be summed up rather neatly in terms of analog write/read methods

do the tests yourself though.... get some cd-r auditting program and notice the jitter errors rise exponentially at higher speeds (wether you can hear them or not)



anyway, right now i have a spindle of cheap and ugly LASER cd-rs that work fine in anything but mainly id go TDK or Acer, as much for convenience and price then anything too technical

ps, ALWAYS "close session" your discs to make sure they play on more systems. im not sure about the technical nerd reasons why this is but im sure one of you does


ps, we got our last album mastered at 301.... jesus... they sure know their work. id not jest at anyone following their work methods there. beautiful studios too! i could live there and be a happy man.

[nicko]

Originally posted by phunkdust
thats interesting... rental dvd's are supposed to have special circular barcodes that sit on the inner leader (the plastic around the hole) to prevent imbalances

interesting about the breaking apart discs tho... I've heard a similar story, where by CD-ROM speed is limited to a maximum of about 52x, because at speeds above that the disc starts to warp from the centripetal forces...

Yeah, I'm going to have to complain about that to them. The guy who was putting on the barcodes was pretty rude as well, he looked like a bit of a part-time gurner (maybe he's on inthemix - anyone from Blockbuster? :lol: )

When you think about it, a cd should be fairly strong on that axis. I don't see how they would break apart, hey..

[DJSeb]

Originally posted by djbc

I will ad this tho'. As soon as you go faster than 1x you start to loose just a little presence / brightness in the top end. We've done endless tests & A/B sessions with this and it's definitely true... even the most "uneducated ears" could pick the difference.


how? CD burners are fed with a digital bit stream. It doesn't matter if the CD burner is getting fed and burning this stream at 10hz or 100Khz. Losing the hi-end suggests that certain frequencies are omitted from the burnprocess. However the burning laser and or plastic cd doesn't know which bits are relevent to the higher frequency samples - the miss burnt bits would be random, and not specific to a particular encoded digital sample, you wouldn't lose the entire 8bit sample of every high frequency component...

Given that each sample is taken in a discrete time, speeding up the burning does not reduce the sample time. If every 10th sample could be and was removed, this would speed up the music played in a cd player!

IF the cd burner was missing bits due to higher burn rate, the error correction encoded into the bit stream would remove them out, considering that cd error correction can fix bursts of 12000 bits long. ref (http://www.cee.hw.ac.uk/~phe/cc/ec4-01.doc)

Perhaps it was another uncontroled component in your test which gave the impression of the lack of the hi end audio, cos I can't see how it would have been the burn speed.

seb

[djbc]

I dunno the technical science behind it, I just know that it IS. Maybe what you mention about error correction is the reason... if faster burnt CD's have more error correction going on & maybe this causes it.
The tests that we did on this involved exactly the same audio, the only difference was burn speed.
Like I said the difference is subtle so really only relevant for your master burns & very important demos.

Question Seb, if it doesn't make any diff. to audio/sonic quality, then how come high end mastering studios bother to do their masters in real time.?

Anyone out there know any tech info at this level that may enlighten this topic?

[driload]

this is a question for Dr Karl im sure!



the high frequency issue is puzzling in the least. if we ignore speed for a second and refer to the PROCESS involved here we can work form the bottom up


ok so we know a laser is firing at a reactive surface, creating pits/valleys which read as digital data

im just flicking through some old audio engineering text books but none have anything relevant to this question...

the Hypothesis is that faster burning speed on DJBC's reduces top end clarity

the variables here include the brand of cd-rs used, the accuracy od DJBC's ears, the cd bruner used, and any software and playback device involved.

i can only tenuously ignore the variable for a second the think about the SCIENCE of why a faster burn would reduce FREQUENCY PERCEPTION.... and i cant think of a thing!


i WILL ACCEPT that faster burn speeds can add jitter error (look jitter error up for yourself) and that is quite important in the digital domain (ie, can make for one of those 1 + 1 = 3 situations) but this should only affect the linear nature of the recording, not specific frequencies



apologies if my 'think as i type' problem solving is a little pretentious and drawn out but im pretty pragmatic about these things.



maybe the best answer isnt one at all.... surely "taking the time to play safe" for your master discs isnt too absurd. any other cd-r audio isnt as important in a time:quality ratio i guess


fucking cd-rs


:lol:

[nicko]

yeah, i hate them too. they really don't do it for me

[djbc]

like I said... I don't understand it... but we hear it... it's not just my ears either... we thought we we're imagining it so we set up A/B tests for anyone who visited... this included musos & engineers as well as music consumers & every time they picked it. We used unmarked discs & all kept eliminating the variables & people kept picking the real time burn as sounding brighter...

right... this has been playing on my psychi for ages & this thread has raised it again... I'm good mates with Dr Karl's "right hand woman"... I'm gonna ask 'em.
Maybe it's to do with data compression. 'cause the audio data is compressed on a cd... so you know how if you're making an MP3 or aiff out of PTools or something (from another file type) you get to choose how fast it's gonna take to make the file... you know good/better/best/tweak heads ... each one takes longer to make the file... the data size is the same but "tweak heads" definitely sounds better (brighter) than "good"... It's got to be something similar... wish I was more nerdy sometimes:meh: ;D

since discovering this... i think I know why most of the home made Cd's & demos I hear sound dull... I thot it was just pc's:p ;)

[DJSeb]

Its intersting to hear that you heard these results from your tests.. I'm very interested to find out why, as I hold my doubts about it being the burn speed, and am convinced that it is another uncontroled variable.

I don't think it is to do with data compression though, as CD audio is "compressed" during quantisation and sampling (during recording) and not after the digital bit stream is realised.....

I wouldn't call the sampling process compression though....

seb

[djbc]

oh whatever - I'm over repeating myself that there were no other variables & we know what we hear:p

Apparently... I was talking to an associate of said Dr Karl's yesterday & he's been researching burn speeds etc. - & some of the newer burners, combined with some new CDr's will do the opposite... less errors the faster you go & higher audio quality too. (We have a Yamaha burner-about 4years old)
I know Karl is pretty busy at the moment but I'm forwarding him questions re all this so maybe the science can shut us all up!!!!:tripping: :lol: ;)

[DJSeb]

I'll take the word of Dr Karl any day without question!!! haha!!

seb

[Sean]

Here's something to chew on.

CD burners in computers are primarily designed for burning data backups. (for the sake of argument let's say they are)

When dealing with computer information, one bit flipped the wrong way is the difference between the letter "A" and the letter "v"

Now that same bit flipped the wrong way or missing can be interpreted by the CD player based on the context of the music, however there's no way for a filecopy routine (moving data off the cd) to guess which way the bit should be flipped when moving data from the CD to the file system.

So it would seem that copying data to the CD would have less tolerance than copying Audio to the disc. If we're worried about errors in the data, seems like we should be equally if not more worried about errors when burning our weekly backup CDs?

just something to think about........

[DJSeb]

interesting point...

It is true that the cd player can fix larger errors due to the context of the music, but cds (and all digital data streams, eg internet) have error codes within the data streams to correct for incorrect bits.

A simple (and highly inefficient) example is as follows.

two bits are transmitted/recorded in a "sample"

The next bit is our error code. If the two transmitted bits were the same, then the error code is 0. If the two transmitted bits were different, then the error code is 1.

Thus if 01 was transmitted/recorded, the error code would be 1. Now if that 01 sample was received, or read as 11, then the error code being 1 would tell us that it was wrong. In the case of the transmission, the reciever could ask for the sample to be repeated.

That is a very simple case, I wanted to illustrate what I meant by error code. More complicated and efficient error codes can also tell us which bit was wrong.

hmmm

<font color="blue"><b>seb</b></font>

[DJSeb]

I asked the head of electrical engineering at UNSW today in one of my classes about this, and he said "impossible, its just a string of 1s and 0s"

hmmm


seb

[djbc]

well there we go then... all speculation over;D :p :lol:

[nicko]

does anyone else think its weird that djseb lives in the act but manages to visit unsw for lectures?

bizarre..

:cue x-files music

[djbc]

:lol: :lol: :lol: :lol: :lol:

[Tax Invoice]

Originally posted by nicko
does anyone else think its weird that djseb lives in the act but manages to visit unsw for lectures?


May he's got himself one of them new fangled jet-backpacks!?
Or a teleporter?

[DJSeb]

Yes, yes thats right. djseb has a jet pack.

or perhaps it is because djseb is at the ADFA campus of UNSW in Canberra.

http://www.unsw.adfa.edu.au/

I'm yet to see a valid reason for why the burn speed affects the hi frequecies alone of the audio though.

seb

[Tax Invoice]

Originally posted by DJSeb

I'm yet to see a valid reason for why the burn speed affects the hi frequecies alone of the audio though.
seb

Yeah, I'm not having much luck in my search on the net, but
that's restricted by a goddam day job (& ITM addiction!) :p

Apparently GF's car stacker won't play burns over 4x. It's not the most expensive system, & skips frequently. -This is yet to be verified by myself.

[djbc]

i'd take a reason... ;) untill then it remains an anomily with our sytem perhaps... still happens consistently.... 'tis very subtle (partly wish i'd never mentioned it :p )

I'm gonna have to wait 'till Karl's upcoming run of shows is over to check out that avenue
:D

[nicko]

Pity. I could see the beginnings of a great moon conspiracy thread.

ps What's ADFA like? is it as good as the ads?

[djbc]

Had a theory last night about error correction jitter affecting the phase (kind of like how on Vinyl pressings with bad out of phase -especially in the bottom end-causes the needle to jump, and for things to sound "bad", -but sort of the reverse of this -anyway...) and that percievably affecting the audio quality.... my search driven by this theory, has led me to the following...

... folks...I think i've nailed it...:)
check out this snippet (http://www.cdrfaq.org/faq02.html#S2-41) (let the page load & jump to target)and then click the link to the canonical jitter discussion,
does a good clear explanation of jitter in A/D pathways... then about 2/3-3/4 down the page there is a section called Can Compact Discs contain jitter? Which is revealing... ;D the whole thing is revealing

I believe this answers many of our scientific curiosities...

happy reading
cheers
bc

[DJSeb]

that snippet doesn't realy explain anything about burn speed vs high frequency audio though...

<font color="blue"><b>seb</b></font>

[djbc]

slow down dude:) ...go to the article on jitter...http://www.digido.com/jitteressay.html and read a bit of the beginning few sections & scrolldown to about 2/3 of the way down the page to the section called Can Compact Discs Contain Jitter.... take some time it's all there...
;)
p.s. i'm not sorry i mentioned it anymore as this whole thread has pushed my curiosity harder to find the answer to something I'd kind of just acepted 'cause i heard it 8-)

[Tax Invoice]

Thanks for that link djbc. I haven't started work thanks to you, now it's 11am! :p
-Some VERY good info there.

-Nice to meet you the other day too ;)
Don't forget to keep me updated re vinyl.

[polarbear]

Yes jitter can create all of those effects; research concerning length & quality of superclock cables in hi sample rate systems shows this to be true.

but a modern CD player with a RAM buffer and a good clock chip should have very low jitter.

old cd player designs would clock using the data coming off the cd. but modern ones have big buffers and good clocks.

jitter present in these systems is more likely to be generated prior to the cd burner / player combination - jitter in multiple digital systems prior to the master.

[Tax Invoice]

What worries me about this is the quality of a master is maybe overlooked due to these buffers over-compensating faults. Would almost be nice to disengage them somehow to allow true analysis in the mastering process (when needed of course). Does anyone know if this is possible?

I know there are progs available to read masters for any inherent faults but can anyone recommend one?

[polarbear]

there is no error correction in hard disk playback.

deliver and archive your masters on a data format - CDROM, DDS, EXABYTE, TRAVAN etc. rather than CD

there are cd players (pro, sony) that you can disable error correction, and get error rates read out.

[djbc]

hey p'bear... did you read it all?... It does actually cover that audio CD's can contain jitter... and it cover's Audio quaility related to burn speeds where they have had the same results as us.
Within this whole discussion, justabout all our questions in this thread have been covered in one way or another.

It covers what you talk about above... that it's in the pathway... not the hard disk (but cdr's can contain it) so yeah if you're gonna get a glass master made then take your tracks in data format *split stereo even better* but for our home made AudioCDr's upping the burn speed may add jitter & affect output quality..
my next course of research is into the deeper specs of our studio's bits 'n' pieces & the crystal oscillator master clock....

& now I know why 301(&other mastering studios) burn at one times... they probably have the whole clock thing consciously sorted out, I'm sure Don must've read about all of this stuff before. & if it didn't affect quality on many levels, then sony & yamaha etc. wouldn't be spending huge amounts on developing technology to correct it.
like I said
happy reading....
I want to know more now.... i'm off to do more research 8-) :tripping:

ps: taking tunes to a mastering facility (like 301) ... if you've got a MAC you don't even have to burn a CD... just take your split stereo mixes on your scsi or firewire drive in 24bit and let them handle all the conversions etc. Eliminates alot of minor issues & reduces the amount od digital processing involved. wouldn't it be nice to be able to afford to do this all the time:p

[nicko]

Wow djbc, you sure managed to write those articles mighty fast! I never could have made up that much technogeekery in 6 days.. :p

[Tristan]

and to think, it was my numpty little question which has started this thread, amazing!

[Tristan]

Incidentally, TDK CDRs work a treat, cheers guys:D