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

LSD KILL!! KILL!!! insect.brain at GMAIL.COM
Tue Feb 12 07:47:08 EST 2008


first: major thanks Paul
second: it wasn't about RFM Trev, and dood, you've got German vinyl
CDR_Acetate_ Max Effect
no matter about the comm release that I already knew might happen


On 2/12/08, trev <judge48 at hotmail.com> wrote:
>
> 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
> >
>



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