[bigshot]

Why would something on the non playing side of a CD make the playing side sound better?

See ya
Steve

 

[Know Talent]

Quote:

Originally Posted by bigshot /img/forum/go_quote.gif Why would something on the non playing side of a CD make the playing side sound better? See ya Steve

it's probably got something to do with electron spin

 

[colonelkernel8]

Quote:

Originally Posted by Know Talent /img/forum/go_quote.gif it's probably got something to do with electron spin

I just died a little. Your post is sarcastic yes? Please, tell me it is... My faith in humanity is slowly slipping away.

 

[Know Talent]

Quote:

Originally Posted by colonelkernel8 /img/forum/go_quote.gif I just died a little. Your post is sarcastic yes? Please, tell me it is... My faith in humanity is slowly slipping away.

...crickets


LOL

 

[nick_charles]

Quote:

Originally Posted by bigshot /img/forum/go_quote.gif Why would something on the non playing side of a CD make the playing side sound better? See ya Steve

I believe the idea is that by adding mass the CD will not vibrate as much as it rotates, i.e it will move in only one dimension and not up and down. This they say means it will not have as many misreads where the laser fails to focus correctly. Of course the added mass places an additional strain on a motor caibrated for a single CD and of course the clamp mechanism is designed for a range of CD thickness which are now possibly exceeded.

I would certainly say UNDER NO CIRCUMSTANCES HAVE TWO CDS IN THE DRIVE AT THE SAME TIME. I tried this trick with a Rotel RCD-02 and it damaged the transport which had to be sent to Rotel for repair..

Whether it works or not is another question.

 

[Pars]

Rick Roberts / Simply Physics used to make a device called an IsoDrive which was a nylon disc which sat on top of the CD to dampen vibrations (apparently). It was marketed for Philips players (most prevalent at the time). I use one on my Rotel RCD-855 and it seems to work; transport mech is a Philips CDM4/19. I have spares...

I wouldn't think that this mat, or others such as the ones sold by Herbie would have enough mass to do anything, though of course some on AA etc. swear by them.

picture:
diyAudio Forums - Increasing CD platter inertia - Page 1

Jocko says that these work and he has used a bunch of them in Philips based CDPs he used to mod.
diyAudio Forums - CD - P jitter Q's - Page 1
DIYHiFi.org • View topic - Tweaking transport servos and optics

 

[joshd]

Quote:

Originally Posted by Pars /img/forum/go_quote.gif Rick Roberts / Simply Physics used to make a device called an IsoDrive which was a nylon disc which sat on top of the CD to dampen vibrations (apparently). It was marketed for Philips players (most prevalent at the time). I use one on my Rotel RCD-855 and it seems to work; transport mech is a Philips CDM4/19. I have spares... I wouldn't think that this mat, or others such as the ones sold by Herbie would have enough mass to do anything, though of course some on AA etc. swear by them. picture: diyAudio Forums - Increasing CD platter inertia - Page 1 Jocko says that these work and he has used a bunch of them in Philips based CDPs he used to mod. diyAudio Forums - CD - P jitter Q's - Page 1 DIYHiFi.org • View topic - Tweaking transport servos and optics

Most of the posts in the links you pasted were against using this as a way to improve optical playback, and also explain why.

Also, by increacing the mass of the disc it is entirely possible to increace the amount of vibration in the disc.

 

[Pars]

Quote:

Originally Posted by joshd /img/forum/go_quote.gif Most of the posts in the links you pasted were against using this as a way to improve optical playback, and also explain why. Also, by increacing the mass of the disc it is entirely possible to increace the amount of vibration in the disc.

Sure... everyone has an opinion. Some may have even tried it. Jocko is an engineer and I respect his opinion on things digital.

Just giving my impressions of actually using one. I can easily go back to stock if I want to.

 

[jazzychu]

I don't think the design of this mat is for weight since it is rather light.

Here is the site you can find product info:
http://www.wei-zhi.com.tw/sitebuilder/page19.ph

I am really surprised that no one bothered to check/google it out before making comments. Again, that attached photo might be too small to read.

 

[Moontan13]

Quote:

Originally Posted by joshd /img/forum/go_quote.gif How is that going to help at all? If anything, the heavier disc having to be spun up might break your reader.

I have a music CD with a self adhesive ring type weight on it from the late 80's. Though it hasn't caused problems in the past, my Lite-On CD/DVD-RW drive growled loudly when I used it to rip that CD to iTunes.

 

[pataburd]

I've had excellent success with the Herbies Grungebuster Mat and even better--much better success, in fact--with the Marigo Signature CD Mat--I consider the Marigo an indispensible component. I also tried the Aurex mat, which didn't bring about any audible improvement when playing discs (some discs seemed to sound even worse). In addition, I've used the Marigo for 3-5 years with various players without any hazard to the reader.

The graphite mat that the OP mentions might be lighter than the Marigo signature, and therefore shouldn't tax the drive as much. I'd be willing to give it a shot! : )

I think, too, that systems capable of higher resolution make audible improvements/differences more readily noticable with disc mats like the one you describe.

The idea of damping the disc and controlling/regulating even spin makes sense to me, due to irregularities (out-of-roundness, variance in depth, etc.) in disc manufacture. CDs spin with an angular velocity varying from about 200 rpm at the outer edge to 500 rpm near the center (i.e. maintaining constant linear velocity from outer edge to center, about 1.3 meters/sec), so comparatively "small" anomolies in the mass distribution of the disc could have pronounced effects translatable to audible anomolies.

Also the absorption/blocking of spurious laser light that can penetrate/pass through the disc through little flecks or "through spots" (where light passes through from the playing side to the label side) also makes sense to me in terms of improving playback by controlling/arresting stray light.

Before doing any critical listening to a disc, I perform the following:
(1) Sand the outer and inner edges of the disc smooth with 220 Fine, followed by open coat, sandpaper.
(2) Wash the disc with warm, soapy water, rinse with hot water and pat dry with a lint-free cloth.
(3) Blacken the smoothed edges, as well as the clear middle band around the spindle hole, with indelible magic marker (part of the Auric Illuminator package).
(4) Surface treat the play side (w/3 drops) and the label side (2 drops) with Auric illuminator liquid.
(5) Demagnetize and destaticize with the Walker Talisman.
(6) Place the Marigo Signature CD Mat atop the disc and load onto disc tray.
(7) Luxuriate in "tweaky" disc bliss . . . : )

As for all the snickering sneerers, my--and many others'--favorable experience with disc mats like the Marigo Signature flies right in the face of your cynicism and, I'm willing to bet in at least some of the cases, exposes opinion-spouters who have neither the experience nor the aural accuity to discern differences with the products they seem so quick to decry and discredit. A distressing testament to the apparent oxymoron of the "Tin-eared 'Audiophile.'" : )

 

[edstrelow]

I tend to agree with pataburd above. Disc sound can be improved with some tweaking. I agree on the sanding and blackening. Auric illuminator is also good, in fact they recommend the blackening of edges and the undersides of labels.

I now polish new discs with a mecahincal disc polisher using very fine grain paste. This gets rid of small scartches and makes the dics really shine.

Discs that are not truly round can be fixed with devices such as the Desk Systeme disc trimmer. It is rather costly but it works. Generally the tarcks of the pits seem pretty circular but these may not be stamped correctly on the plastic disc. With some discs you can feel and hear them vibrate on a portable cd player.

I have had mixed experiences with mats. All did something to the sound, generally slight, but it was sometimes hard to tell if it was an improvement. The cd on cd trick goes back to the early days of cds. Obviously you need to be aware of the possibility that some mats will not work with some players.

My most success was with the Herbies Grungebuster which seemed to add some bass and dynamics but after I got the Stax Omega 2A phones it seemed as if this was muddying up the bass and I stopped using it. It seems that a tweak may or may not be an improvement depending on how it relates to the rest of your system.

Because I was already using some kind of weight on my discs, possibly the Grungebuster was too much. I believe Herbies has another product now designed to stay on more or less permanently.

I use other stick-on weights more or less permanently attached to discs whenever I can get them. I believe this avoids some of the problems with mats coming loose, sliding and jamming up mechanisms. The Audioquest stick on rings referred to above seemed to be the best but are long out of production. I was able to get a closeout of Alsop's sorebethane rings which adhere to the edge of the disc but they no longer have any and I am running out. You can still get various stick on covers for cds which will add some mass.

I say try them and see what you hear.