CD-R quality (was Re: Shameless CDR vs CD questions)

[trev]

hi paul,

i used to use verbatim data life plus. the last lot were on data write
i burn them one at a time at16 x on a 52 x burner (nero burning rom)
then print the on-body on an epson photo r265.
i also print, cut out, assemble the covers by hand
each cd takes 15 mins to produce, not counting the 20 -30 hours or so to, 
master tracks, design cover etc

the amount i sell on rfm makes it uneconomical to mass-produce

most emergent bands who play at green festivals (real festival music bands) 
find it uneconomical to produce anything but cdrs

i think it's better to sell cdr's than to not have your music heard, apart 
from live performances, which would be the choice for a lot of of these 
bands

i'll be buying jap cdrs from now on...are there any other jap branded makes 
that you can recommend.
cdrs are now so cheap that it's madness to buy any but the best

i buy from svp communications (blankdiscshop)

a commercial re-release of max effect is on the cards soon...maybe

it's quite refreshing to speak to someone on this list who obviously isn't 
mentally deranged .... lol

best wishes,

jt

REAL FESTIVAL MUSIC - RFM   http://www.realfestivalmusic.co.uk
 Festival CDs, Photo Reviews, Festival Listings, News, Healers


----- Original Message ----- 
From: "Paul Mather" <paul at GROMIT.DLIB.VT.EDU>
To: <BOC-L at LISTSERV.ISPNETINC.NET>
Sent: Tuesday, February 12, 2008 11:05 AM
Subject: CD-R quality (was Re: Shameless CDR vs CD questions)


> On 12 Feb 2008, at 9:04 AM, The Intelligentsia wrote:
>
>> Just _what_ is the deal here???
>> In my past experiences I have had 2 problems:
>> 1) CD's with scratches either so deep or so many of them that they  cause 
>> the
>> music to get "hung up", making a very fast rotational clicking noise
>> 2) Ozric Tentacle's original Dovetail CD's having an apparent "ink" 
>> problem,
>> whereupon it would eat down into the cd, and cause the music to  become a
>> horror noise rather than music
>> *BUT THEN RECENTLY, I tried to copy some HW CDR's at a friend's, and 
>> he's an
>> ass, as well as a friend, so of course they were done at 4x normal  speed 
>> and
>> DID NOT come out right*
>> *come to find out, he can record actual cd's at 4x with no problem,  but 
>> NOT
>> CDR's*
>> *so what's the deal with THAT?????*
>> *then we get to Trev's Max Effect CDR......not normal here either- 
>> what
>> mine does, is it has occasional drop-outs in the music, and will  tend to
>> jump ahead in the tracks*
>> *now admittedly my players are cheap, but they only malfunction with 
>> this
>> one- also, there are a fair amount of blemishes on it because he's a
>> musician, and most don't know better, etc*
>> *my point being: I thought none of this stuff was supposed to happen 
>> with
>> CD's/CDR's!!!  I thought only hang-up's would occur when too many 
>> scratches
>> or a scratch that is too deep is present*
>> *fill me in folks, would ya please!!!!*
>
> Here's the gist of it: CDs and CD-Rs use different physical  technologies 
> to encode the music layer and so are prone to degradation  in different 
> ways.  In particular, CD-Rs are less robust than CDs and,  usually, 
> scratches on the underside are the least of your worries.
>
> Greatly simplified, CD-Rs are basically a shiny reflective layer with  a 
> layer of organic dye underneath, all encased in plastic.  Music is 
> recorded on the disc by the CD-R drive laser operating at higher than 
> normal read power.  The higher power causes the organic dye layer at  that 
> particular point on the disc to change its chemical properties  and, 
> importantly, to become optically different, reflectively  speaking. 
> (That's why they call it "burning" a CD-R.)  So, altering  the organic dye 
> layer is how the 0s and 1s that encode the disc's  contents (including 
> music) are recorded.
>
> This presents two major points of failure as far as disc longevity and 
> playback quality is concerned: the quality (and stability) of the  organic 
> dye layer, and the toughness of the reflective label layer.   If the 
> reflective label side is easily breached or scratched this can  cause 
> damage because at those points on the disc there is now nothing  to 
> reflect the read laser back.  So, discs with tougher reflective  layer 
> sides are better.
>
> If the organic dye layer degrades then this leads to a general  increase 
> in the Bit Error Rate (BER) of the disc.  Once the BER  becomes too high 
> (to be compensated for by the built-in error  correction capabilities of 
> the CD format) then you start to get  playback problems.  The organic dye 
> layer can degrade for a variety of  reasons: poor storage; excessive heat 
> or humidity; etc.  Remember,  though, that the organic dye is a chemical 
> and so, as with all  chemicals, can vary in quality due to the materials 
> and processes that  go into manufacturing the chemical.  So, low quality 
> dyes may not be  as stable over the long term and might degrade faster 
> than higher  quality dyes.  (A lack of stability causes the optical 
> properties to  degrade over time; 0s degrading into 1s; etc.---somewhat 
> similar to  the "CD rot" that afflicted the Ozric Tentacles Dovetail 
> pressed  CDs.)  Low quality dyes might also make the original recording of 
> a  lower quality in the sense that it is closer to the acceptable margins 
> of engineering tolerance (pits and lands size, etc.) allowed by the CD 
> format.  For example, if a dye is lower quality, it might not change  its 
> state well-defined enough when burning at high speed, resulting in  a 
> recorded disc that is already at the margins.  Such discs will be  harder 
> to play on a variety of different hardware and are less likely  to have as 
> long a useful life.
>
> As for underside scratches, the ones that do the most damage are the  ones 
> that run parallel to the CD spiral direction.  Ones that radiate  straight 
> out from the centre to the edge are the least damaging  because they 
> affect less contiguous runs of bits, and so are the  easiest to overcome 
> via the CD format error correction.  Likewise,  surface scratches that are 
> not too deep are usually not problematic  because the laser focuses past 
> them and so, optically, they don't  present much of a challenge.
>
> To sum up, even though lots of people will no doubt disagree, the main 
> factor on the LONG TERM life of your CD-Rs is the quality of the disc  and 
> how it is stored.  Buy good quality discs and you will have less 
> problems.
>
> Again, this will probably kick off an argument, so take it for what  it's 
> worth, but the usual rule of thumb is to try and avoid "Made in  Taiwan" 
> discs and look for "Made in Japan" discs.  There is a big  quality 
> difference in the fabrication plants and the consensus is that  the 
> Japanese ones are higher quality.  There aren't that many  fabrication 
> plants and most of the varieties of discs you see are just  companies 
> branding product from some fab or other.  Unfortunately,  most of the 
> discs you find in the shops are of the made in Taiwan  variety.  In the 
> interests of full disclosure, I buy unbranded Taiyo  Yuden discs.
>
> I hope this helps.
>
> Cheers,
>
> Paul.
>
> e-mail: paul at gromit.dlib.vt.edu
>
> "Without music to decorate it, time is just a bunch of boring production
>  deadlines or dates by which bills must be paid."
>         --- Frank Vincent Zappa
>