Over on Audio Asylum almost same question today..
The Cd can be slightly warped. Since the machine only grips a CD bt the center hole, and no support around the rest of the disc, if the center hole is not level with the rest of the disc, (warped) the disc will cause vibrations as it rotates.
The miracle here is that the lens has to be really really close to the Cd surface to read the disc, and follows the vibrating discs perfectly. Amazing!
So, if you do not want the discs to vibrate, toss the ones that do it.
Sometimes those aftermrket 'disc stabilizeers' help with this.
Also: here is a perfect 'oppo'rtunity for some tweak genius to make a device to flatten discs that vibrate.
Or, buy a Pioneer with the inverted 'stable platter' which supports the entire disc.
If you can track it down to certain cd's that are vibrating, try them in a different player, maybe it's the Oppo that is the problem. I'm not sure a slight warp would cause a vibration, it may be more likely an off center (out of balance) disc can cause a vibration, those discs can be cut to even them out. I only own several hundred cd's but have never seen this problem, good luck tracking it down.
I experienced it with a different player, a Denon DVD player which I soon returned to the retailer. Only happened with some CDs but the same CDs played fine in a couple other CD players I owned.
leatherneck why not do what i do with warped CDs. I put it under enormous amounts of heat and pressure. These conditions will form diamonds naturally.
Thanks for sharing again. Your posts are often really informative to a novice like myself.
Regarding disc stabilizers. Would those a Carbon Fiber CD Mat help? What stabilizers would you recommend?
My Oppo BDP-83SE and stock BDP-83 vibrate a bit quite often regardless of disc. Be it an SACD, Blu Ray Disc, XRCD or CD. I thought the vibration was normal. I just put 2 5 lb weights and sheet of Acoustimat under the weights to help with the vibration. I'll keep doing more checks to see what discs cause the most vibrations. I'm pretty careful with my CDs. I wonder how they could have warped.
Thanks for the responses.
Elezabeth, I don't think it is warped. I have an aftermarket stabilizer disk and it lays perfectly flat on the CD in question. It also has no noticable effect on the vibration.
Mjglo, I don't currently have another player in the house, but that's a good idea.
Ddd1, Did you use a different Denon CDP of the same model and get different results? Or did you change players completely?
I am hoping to hear from Oppo owners as to whether or not they can reproduce this effect.
"Ddd1, Did you use a different Denon CDP of the same model and get different results? Or did you change players completely?"
The Denon was a DVD player. The players/transports that the same CDs didn't vibrate were different makes altogether. (ie. Simaudio Moon CD-1, CAL Delta, a couple expensive Sony universal players).
the millenium carbon fiber mat reduced ad eliminated vibration on my friend's transport.
it is sold by aaimports. you can mention my name when you call brian. my name is roy harris. i own one.
The Cd spins so fast, and the twist in the central area so tiny, you would not be able to see it. The biggest flaw in transport technology is that the CD is held only at the inner 2mm or so of the entire disc. So that central area can be off by only a few hundreths of a millimeter, and it will vibrate, especially if the disc is also very slightly off balance.
Like I mentioned, The one disc player that had a solution to this was the Pioneer Elite "Stable Platter" where the entire disc was supported, and the disc placed into the player upside down on a CD sized turntable.
I wonder why no other manufacturers ever used that?
For some of the problem to be an individual players fault also makes sense, as the typical magnet clamp is pretty flimsy, and might have a manufacturing error that makes it more likely to not seat correctly. If this is the problem, opening the top up and checking the little top puck might help. The usual way it is in there the top clamp is held in a plastic holder, that only loosely/approximately lines up the spinning motor and the upper clamp. You can watch it load with the top off and see how it clamps on some of the vibrating discs. Perhaps all you need to do is push/bend the plastic holder of the top puck down a fraction of a millimeter. (I have done this)
I'm not so sure the problem is discs that are a bit off-centered. I once had a Yamaha S1500 player that would do this vibrating on occasion. But when I bought a Pioneer DV-79AVi the same discs played perfectly.
My opinion: a design flaw in the Yamaha or just piss-poor tracking ability.
I noticed a similar vibration on my PC's DVD drive, may be a clamping mechanism, don't know for sure.
I have a CEC top load transport which I use a Herbies Grungebuster adhesive mat on the bottom of the CEC puck for damping.
A De Mat (Van Art Speak) rubber and carbon fiber impregnated mat is also placed on top of the CD to very great effect, but I would not recommend this one for tray loading transports or players, they could jam.
Elizabeth I have wondered why others have not used the same idea as pioneer as well. Seems like a good idea.
I recieved this answer from a tech that has worked on my stuff.
You're right the Oppo drive does vibrate a lot and it's normal. The Oppo drive spins the disc 200x faster then the Ikemi did. The older style plain CD drives were not high speed computer ROM drives with no RAM buffer memory stage to totally eliminate jitter. With dedicated CD players, jitter can be off the charts if the cd was cut out of round or vibrates alot. With a blu ray player, the data is stored and updated into a FIFO RAM buffer many times a second. No data goes out to the rest of the player until it is jitter and error free. Vibration and out of round or scratches do not affect the high speed re-reading ROM drive type players.
I have a nice Oppo BDP-83SE, and I have also found this to be true... most discs play fine (smooth, quiet, and vibration-free when I hold the cabinet)... however, some (quite a few) discs cause vibration, mainly those from the library or rentals, and I have pretty well confirmed that they cause vibration because they are a wee bit unbalanced in the horizontal plane(not warped), due to the stickers, barcodes, clear lamination, etc. that are sometime stuck ontop of these discs... I've proven this by taking a "good" CD, sticking a short piece of masking tape off to one side (to create a small imbalance), and then playing it... sure, enough, I start to a get a vibration right away... adding more tape makes it worse, removing the tape removes the problem... Oppo is willing to take in my unit (at my ship cost + hassle and risk of ship damage...), HOWEVER, if this is a problem inherent to *all* 83s or 83SEs, then they won't actually be able to fix or change anything, and it will be a big waste of time... Q: what ended up happening with your unit?... did you send it back and get it fixed or ???... can anyone else comment, or better still, try the masking tape test and report back with your findings here?.. thank you!
I agree the culprit is much more likely to be unbalanced vs. not flat. The principle is no different from what you face with car tires. Which begs the question of could there be such a service as a "CD balancing " service" and would it be practical.
That's one of the things that the Audio Desk CD lathe does. I do both sides which trues and balances the CD.
An excellent example of why it's so important to obtain true level of the CD transport, which, as fate would have it, cannot necessarily be obtained by sticking a level on top of the CD player due to tolerances of manufacture. A non-level transport just exacerbates any tendency of the disc to wobble or flutter.
I can say 100% for sure that it happens with unbalanced discs, much like a car tire will vibrate if not balanced... (of course, it might also be caused by warped discs, but that's an other matter...)
the unbalanced condition can be caused by add-ons like barcode and ID stickers, anti-theft strips, clear laminations, etc. that rental places and libraries sometimes attach to the top surface of discs... in fact, I can simply look at a disc and predict whether or not it will cause my BDP-83SE to vibrate, and by how much
one would also expect that an out-of-round or slightly misplaced center hole would cause a vibration, since that would cause an imbalance
I've noticed that most commercial discs (unaltered) will play smoothly, but not always "perfectly" and there might be some very minor vibration... I have noticed that CDs that I've burned myself are actually the most consistently perfect... perhaps they have higher manufacturing tolerances and no artwork?
I have discovered that I can "fix" a problem CD simply by adding some masking tape on the opposite side of the offending junk, to act as a counterbalance... I just did that to a really bad disc, by adding 3 layers of masking tape (a short strip approx. 1.5" long)... before was vibrating noticeably and I could even hear banging in the cabinet, then after, almost zero! (luck guess as to how much weight to add)
I have tried testing some especially bad discs in 2 other disc players: my ancient 1987 Sony CDP-302, and my Oppo 980H... the Sony played discs perfectly with virtually nothing felt! (quiet and dead steady)... the Oppo was also OK, but did show some vibration still, but only maybe 10% of what the BDP-83SE did
SO THE BIG QUESTION:
is there something wrong my particular BDP-83SE unit, ie., one that Oppo will be able to fix somehow, OR, is this apparent hyper-sensitivity to disc imbalances INHERENT with BDP-83s?... maybe there is a reason for it?
If someone could please try adding some masking tape to a known perfect disc, then playing in their BDP-83 and testing for vibration, that would be HUGELY appreciated...
it would help me decide whether or not sending into Oppo would just be a waste of time & resources
I have been using three 1 inch strips of black plastic tape applied radially on CDs for some time. I suspect the tape reduces vibration of the CD whilst spinning. Of course there are a number of CD mats that address vibration, too.
Geoffkait: in my situation, I am applying the tape to correct (ie., offset) any *imbalances* a disc has, same way that a tire garage puts lead weights on the rim of a car wheel
I am guessing that imbalanced discs do not actually "vibrate", but rather that the entire disc drive/transport unit absorbs the forces generate with each revolution, and this then gets transmitted out to the entire chassis... I seem to feel a definite side-to-side motion in the vibration, not so much all around... but obviously it does eventually get mixed over
I have to wonder how all this shaking affects sound or video quality... given all the effort put in to "reducing and isolating vibrations" by manufacturers (incl. Oppo), wouldn't the severity of these vibrations make that look like a joke?
heck, a really "bad" disc even caused my wife's drink to shake after she had placed it ontop the Oppo the other day!.. she pointed it out to me, unprompted
still hoping to hear from other BDP-83/83E owners who can play a purposely imbalanced disc, and if they get chassis vibration even for a very small imbalance
I have the same problem with my Oppo player. My old sony has zero vibration with SACD's while the Oppo shakes. Did you ever find a solution? Does the unit need to be repaired? I'm wondering if the old sony maybe spins at a lower rpm, but I assume all SACD's require the same rpm, new or old player.