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CD Player Modification Voodoo?


Kenhorns

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Anybody ever heard of doing this? What's the technical explanation behind it, if in fact it's not just superstitous Voodoo?

Just bought a 3pc Onkyo setup at a Garage Sale Saturday for $50. Onkyo A-RV401 amp, T-403 Tuner, and a DX-C101 CD Player. Best I can tell this is 1991 stuff. Seller buys/repairs/sells audio stuff. Appears to be a knowledgeable electronics tech.

In conversation regarding CD players he stated that they produce weird harmonics within their cabinets. He suggested the best and simplest modification that one could do to improve sound quality of their unit is to purchase a 12"x12" piece of pre-sticky linoleum tile at (say) Home Depot, cut to size, and stick to the inside top of the player's metal case cover. Supposedly, remediates these harmonics.

He admitted it sounded like Voodoo, but insisted that it be tried.

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Guest David H

As with all myths, legends, and audiophool voodoo, there is usually some truth buried in the fabricated story. On certain poorly balanced cd's and dvd's the cover on my player would start humming and that harmonic would transfer into vibration throughout the unit and make the player skip occasionally, to cure the problem I lined the inside of the cover with adhesive back mastic ie. Dynamat, Fatmat etc even a piece of adhesive flooring may have done the trick. The lining on the inside of the cover acts as a vibration damper, thus changing the covers resonant frequency. Problem solved.....Myth revealed.....Although cd's and dvd's just produce zero's and one's.....Blurrrrrryyyyy Zerroooossss and oneeeeeesss are not all that good.

I have seen many vibration dampers on the market that cost hundreds of dollars ranging from been bags to special cryogenically treated wood blocks.

Get out your BS buttons.

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Underwood Hi Fi is big on this modifying Jolida players. I have never heard one but it seems like BS. It seems like something that works in one area, like maybe dampening for turntable resonance, and then it has to be done to everything.

My favorite is spikes. Use a pointy spike to stabelize a speaker through a carpet. Good idea. The spikes look cool so use them on the bottom of everything? Why? Rubber feet have a very high friction coefficient and work very well to stabelize a component.

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Interesting comments so far. I do not think my Garage Sale Voodoo Technician had case or cover vibration in mind when recommending the linoleum tile damping....rather, something about the laser producing weird harmonics inside the cabinet. Sorry I left that out in original post question.

Can/do lasers produce undesirable harmonics that impact the music negatively? If so, how do u remediate, or should u even bother?

Or, alas, is this really just "audiofool voodoo"?

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And think of the fine tuning possiblities.... the small blue racquetballs, handballs, optic yellow, orange, or white tennis balls (do they still come in white?), really fuzzy new tennis balls, or practice tennis balls worn smooth.

Great post. I need to better isolate my turntable better and this sounds like the most affordable approach I've seen ... and potentially looks crazy enough to be fun.

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Ok, the ball jokes were fun and the ball leveling systems very informative, BUT, I still don't have an answer to my question, or you guys did answer and I just continue to be a dumb novice, or you guys are being nice and just ignoring my ignorant question.

Do lasers within CD Players produce any weird harmonics that need to be mitigated? and, (see this original post), is linoleum tile a viable remediator?

As an anology, please recall that for instance on Cornwalls, inside cabinet standing waves, I have learned from this Forum, are mitigated by adding foam/philloux paper baffling to the inside cabs.

Is there any similarity to CD players and laser harmonics, or again, is my Garage Sales Tech just espounding Audiophile Voodoo?

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I've never heard of laser harmonics, but vibrations can be an issue in certain components. A few months ago, I put an unused wooden cutting board under my CD/DVD player and the sound improved noticeably. 7 pounds of solid maple seem to soak up any vibrations that enter or exit the player.

As well, I placed the Dx38 processor on top of the player on three pieces of industrial vibration-absorbing rubber, so the stamped-metal top would be unable to vibrate.

The result was a bit more midrange clarity. Maybe the top of the case had an inaudible buzz that was messing up the sound, I don't know, but it sounds a bit better now and it cost me nothing.

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There are a lot of tweaks out there......some seem rediculous. The reduction of vibrations seems legit to me. I have not tried it yet.....but I intend to.

I have found that the little things count just as much....if not more....than a major upgrade in gear.

Don't know about laser harmonics other than vibrations may influence them in some way or another. Sorry couldn't be more help........but we did get to talk about blue balls. [:P]

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In MHO, it is voodoo.

The laser puts out a low level light signal which is infrared, meaning below the freqs of visible red light. It is doing nothing but illuminating the pits in the CD-ROM. The laser aspect means it has a single "frequency" of light. This helps in getting a good image of the pits. The rainbow effect we see in broad band white light would cause problems.

There are no IR harmonics and no reflections around the inside of the box.

There are potential sound sources inside the box from the drive motor which spins the disk and the other motors which focus the microscope which looks at the pits and also the motor which moves the tracking head along the spiral of pits on the CD-ROM. It is impossible for me to believe these sounds or vibrations are bouncing around the inside of the box enough to cause mistracting or modulation which would interfer with playback.

Consider that very similar mechanisms in computer driver read and write at 4x or higher speeds without problems. We sometimes hear the buzz of the drive motor at high speed.

There are many tweeks out there. The vibration based tweeks all assume there is something going on which gets in the way of accurate reading. IMHO these are left over from vinyl record players which do need vibration isolation but turntable generally have this.

Your point out internal damping of e.g. the Cornwall is not technically inaccurate. In that case it is necessary to absorb sound waves created by the back of the bass speaker diaphragm. But there is no loud sound in a CD player. If the top of the cabinet is buzzing, I would begin to think about the value of the tile dampener, but that is not happening.

If making the tweek keeps you happy, by all means do so. But in my view, there is a big psychological effect to any tweek if the maker has faith. There is always the suspicion that a manufacturer could have done just a little bit more and we at home can complete the needed cure.

But as I always say, You can't make things better by solving a problem which doesn't exist.

WMcD

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The effects of controlling vibration in electronic components may seem minimal, but it seems to be an idea that's catching on with high-end manufacturers. Stiffer chassis, cast aluminum housings instead of bent steel sheet, resonance-control feet. And that's just in amplifiers and other components with no moving parts. The concept should apply even more in disc players.

Maybe vibration was not significant in the past, but as distortion continues to be reduced and clarity improves, what seemed like hair-splitting in the past may be starting to have audible effects.

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Thanks Gil,

I suspected it was Voodoo - searching the web for CD Laser tech articles recently, produced no discussion or observance of any generated sound harmonics, but as stated before, I'm a novice and not a qualified guru.

So, no trip to Home Depot and no $1.25 outlay for linoleum tile damping material, for me.

Again thanks,

I am now considering purchasing "blue balls"!

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