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    Audiophile Question, please ??

    I have discovered a strange issue with my CD/DVD player due to misalignment of the clamp. The transport was making a ticking noise and I had a look at the clamp. It turns out that the problem was not a vertical alignment, but rather a horizontal alignment from left to right. This was verified by the grey paint being worn away from the clamp holder plate on the right side of the clamp. The right side of the clamp was sometimes (but not most of the time) scraping on its right side, thus causing the ticking sound. I MAY have corrected this by removing the four screws from the top plate which holds the clamp, putting pressure on the plate from left to right (there was minimal movement, but it as enough) and reinserting the screws tightly all the while hold the rightward pressure on the plate.

    Something else strange: I noticed that I can reload the same CD several times and sometimes it spins more eccentrically than other times. I do not know if this is normal, or rather indicative of a systemic problem. However, I decided to remove the cap (counterweight?) from the top of the clamp and leave it uninstalled for now. The player seems to be working fine without it and the spin of the CDs seems to be less eccentric overall without it.

    I am beginning to wonder if this player has perhaps sustained some minor shipping damage (more than once?). I imagine that the delicate suspension of the laser tracking assembly can be compromised without any visible damage to the player itself or even to the outer shipping carton.

    By the way, the really bad CDs are still acting crazy. Thus far there are only three like this. Although they will play in a plain old CD player. This is likely a separate issue from the one at hand.

    What do you think about my leaving that cap off the top of the clamp? (The transport was made my Matsushita.)

    Many thanks!!

    #2
    Originally posted by Menschenstimme View Post
    I am beginning to wonder if this player has perhaps sustained some minor shipping damage (more than once?).

    By the way, the really bad CDs are still acting crazy. Thus far there are only three like this. Although they will play in a plain old CD player.
    You obviously have a very low tolerance for defeat! What is a CD player worth these days; $20? I tend to suffer from the same deficit; spending countless hours attempting to fix some worthless contraption, that at from inception, should have been tossed into the trash bin!

    I was first confronted with the new ethic, about ten years ago when buying a new Sony VHS recorder from my familiar local dealer. He explained the warranty: If anything goes wrong in the first year, bring the defective unit in, and we will exchange it for a new one.

    So what happens to the defective units? They are summarily tossed into the trash. Sony doesn't even want the defective stuff sent back to them! It is far less expensive for Sony to simply manufacture a new unit, than to fix a defective one!

    CD/DVD players are not all created equal. What might work fine on one, won't work at all on another. I've recently been trying to figure out why a Divx movie kaacks at around 90 minutes on my old Philips DVD player, while it plays just fine on my computer.

    1. I recorded it to a different DVD. No luck.

    2. I bought a new DVD player ($48). Still no luck.

    3. The new DVD player has a USB port, so I tried playing it from a USB stick. Same nonsense!

    Some players are simply more fault-tolerant; and can pick up lost tracks, and continue on with the movie/music better than others.
    2008: Phoenix III/44

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      #3
      Thank you for trying to help, Clarion!
      The player in question had a list price of $3000 when it was new in 1998. I bought it for $700 as a barely-used second-hand unit. Perhaps it sat around too much without being used and this may be part of the problem?

      Comment


        #4
        Originally posted by Menschenstimme View Post
        Thank you for trying to help, Clarion!
        The player in question had a list price of $3000 when it was new in 1998. I bought it for $700 as a barely-used second-hand unit. Perhaps it sat around too much without being used and this may be part of the problem?
        Wow!! How time$$$ have changed!!

        As for sitting around for a while without being used; I've experienced that in the past. The slider gets all gummed up, and can't reach the necessary extremities of travel!
        2008: Phoenix III/44

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          #5
          Originally posted by Menschenstimme View Post
          Something else strange: I noticed that I can reload the same CD several times and sometimes it spins more eccentrically than other times. I do not know if this is normal, or rather indicative of a systemic problem. However, I decided to remove the cap (counterweight?) from the top of the clamp and leave it uninstalled for now. The player seems to be working fine without it and the spin of the CDs seems to be less eccentric overall without it.
          Eccentric spinning discs are normal to some extent. The laser arrangement usually counteracts this.

          Using heavy clamps on CD players is a bit of nonsense. Turntables (for vinyl) turn at the same speed throughout the whole record, but CD players turntables have to slow down as the recording progresses due to the equal spacing of information on the CD and the disc is read inside out. Removing of some weight of the clamp is therefore not such a bad idea (less inertia to overcome for the spindle motor - and indeed less wobble when the CD isn't inserted perfectly centric), as long as the clamp does take the CD with it and doesn't slip.

          Normally, slipping CD's can lead to a ticking transport, as the transport struggles to counteract the slipping and find tracks. Some people get around that by sticking some tape on the inner bottom side of CD's - the part which goes onto the spindle - to get more friction.

          I have a Naim CD player which had the same ticking problem due to a worn spindle nextel ring. Some CD's played fine, but some of them weren't playable at all. I bought a new magnetic clamp for it and now the unit plays and tracks everything again.
          Last edited by sarqoz; 10-21-2010, 02:59 AM.

          Comment


            #6
            As for CD's they have to comply to the "Red Book" standards. However there is some deviation in thickness of the CD discs themselves, worsening some of the slipping issues when you have a particularly thin one.

            Then you could try to copy the CD (use disc-to-disc copy) and use the copy to be enjoyed on your hi-end system.

            Comment


              #7
              A thing you could also try: try to "clean" your spindle and/or clamp surfaces with blue-tack. Be sure to knead the blue-tack sufficiently to make it soft and tacky. Then carefully tip around the contact surfaces, removing dust and other stuff. Be very careful as you do this, since the blue-tack is capable of pulling that grey paint you mentioned (I guess that it's Nextel too) with it.

              Don't go anywhere near the laser though!

              Hope this helps!

              Comment


                #8
                Many thanks, Sarqoz !!

                Your responses are most useful and thought-provoking, and thus very helpful.

                My transport already has a built-in magnetic clamp and now that I have removed that extra weight (which is what I presume it to be) from the top of the clamp, the player does indeed appear to work better.

                Getting back to my "recentering" of the clamp over the spindle: I wonder if the unit may have been stored on its side for an extended period of time instead of right-side-up, thus causing the off-center effect? Whatever . . .

                Thanks again!

                Comment


                  #9
                  Originally posted by Menschenstimme View Post
                  Getting back to my "recentering" of the clamp over the spindle: I wonder if the unit may have been stored on its side for an extended period of time instead of right-side-up, thus causing the off-center effect? Whatever . . .

                  Thanks again!
                  The transport in my Naim CD player is suspended by tiny springs to aid the absorption of vibrations. On this particular series Naim installed "transport lock screws" prior to shipping, to lock the transport so that it can't move. Before use you have to remove them. Other units using a Philips transport (ones with a swing type of arm - identified by a curved cut-away in the transports base plate) sometimes did have the lock screws too, because the whole transport sits in springy contraptions too. I don't know your transport, and maybe it's a dumb question/ suggestion anyway: but have you checked that the transport isn't locked, offsetting it that way?


                  My Naim CD player is of a top-loading design: you have to manually remove the magnetic clamp before putting in a CD and then you have to put the clamp back on. It's possible to loose the clamp though, falling through slots into the CD players case. Then you have to dismantle the whole thing to get it back. The player has seen almost 20 years of service and is still going strong. I'm keeping a little stock of cheap Philips CD players that use the same transport for future donor use (they don't make 'em anymore), should my original transport give up.


                  Modern times heralded some odd things happening in the audio department. Ever been to a hi-fi show recently? At first you see and hear some seemingly good things, but at further glance one sees some over-engineering going on: massive clamps on CD players, insanely massive speaker and power cables, speakers that weigh a ton; sometimes made out of expensive material like marble or jade, turntable tonearms suspended by air (!), plasma tweeters etc. BUT THEN you take a peek at the front-end and the whole gathering of 21st-century technology is driven by tubes! Yes: 1910's technology!

                  The selected recordings used during these show are something to rant about too: Take Five, Radetzky March, Danse Macabre - just some nice music without being too complicated to scare off potential customers, but hey: here you sit, listening to an audio system coming at a multiple of $100.000, belching out the Radetzky March!

                  That always makes me think of this Turkish Delight film scene:

                  http://www.youtube.com/watch?v=W6GIM7oHl7Q

                  Comment


                    #10
                    Thank you, Sarqoz!

                    No the transport is not locked - but I appreciate your exploring all possibilities. But there's more:

                    Last night I played a CD of mostly quiet pipe organ music and I am ALMOST certain that when it started there was no transport noise. Then, near the end of the CD, on a quiet passage, I was very disappointed to discover that the noise had returned. I tried several other CDs of the same label and some of them caused transport noise and some did not. Thus, one cannot actually say that the transport is completely malfunctional. A large part of the mystery here is: Are the CDs at fault, or is the transport marginal?

                    Let us consider this idea: The way this Matsushita CD/DVD transport loads, the drawer pulls the CD in. Then the entire laser/spindle assembly rises up to push the spindle through the center hole in the CD and engages the magnetic clamp/puck. When there is no CD in the transport, the puck rests in its hole in a metal cover that sits atop the transport mechanism. When the spindle engages the puck, it positions the puck in a very precise position within its hole so that it does not rub any edges of the cover while the CD is playing. The idea I have is that sometimes the puck is not being precisely positioned by the spindle, causing the puck to rub. (I know that the puck rubs sometimes because I have watched it do so.) I must interject the thought that this design is overly precise with little margin for error or play in the position of the puck. This appears to be an oversight in the design. For example: During play, the laser, spindle, CD and puck are all one joined assembly. If a certain CD is slightly thinner or thicker than it actually should be, then the edges of the puck can rub on the edges of its hole in the cover. Or, if the laser/spindle assembly are not always parking precisely in the exactly correct playing position, then the puck will rub on its cover. Perhaps the suspension (whatever that may be) of the laser/spindle assembly are out of specs due to age, storage, shipping shocks, or an adjustment error? If the designers had given the puck a wider channel instead of having it just barely miss the edges of the cover, the laser/spindle assembly as well as CD thickness would have some margin for error. As it is, the design is very fussy unless all conditions are ideal.

                    I will have another look and see if there is anything more I can do. Please let me remind us that CDs that are causing transport noise in this unit, will play in a plain old CD player just fine.

                    The big question is, if I decide to have this unit professionally serviced, can I realistically expect the technician to be able to isolate and correct the problem? Shipping and repair will be expensive and the shipping alone will risk further damage. Oh well . . .

                    Comment


                      #11
                      The big question is, if I decide to have this unit professionally serviced, can I realistically expect the technician to be able to isolate and correct the problem? Shipping and repair will be expensive and the shipping alone will risk further damage. Oh well . . .
                      NO. I had my Meridian 500 send back to be repaired after it started skipping on cd's when it had been some time in use. It came back after a few months and while it did play correctly a few weeks it again started to behave like before repair. And the repair costed more than a mid-price new player.

                      apart from that, I think you are over-reacting. Cd mechanisms do make noise. Part of it is from how they are designed to work. Like the drive of the sled that houses the laser. This doesn't move smoothly and uniform but it oves in small jerks while the magnetically suspended lens assembly corrects for this. So what you hear may be just the way it sounds. Very similar to my sony dvd/cd/sacd player. (which I hate for other reasons)

                      Comment


                        #12
                        Thank you, Havoc; but I can assure you that this noise is not normal by any means.
                        Less than 5% of the CDs in my collection make this tracking noise. The other 95% play silently, without transport noise.
                        99% of my CD collection plays silently in several other plain old (non DVD) CD players I have around the house and also in a very inexpensive CD/DVD player that I have. Transport mechanisms are from Philips, Sony and Matsushita.
                        Thank you for trying to help!

                        Comment


                          #13
                          Originally posted by Menschenstimme View Post
                          Perhaps the suspension (whatever that may be) of the laser/spindle assembly are out of specs due to age, storage, shipping shocks, or an adjustment error? If the designers had given the puck a wider channel instead of having it just barely miss the edges of the cover, the laser/spindle assembly as well as CD thickness would have some margin for error.
                          When there was major damage done to the transport you wouldn't be able to play that much. Please be reminded that you can play around 95% of your stuff, which is within the Gaussian distribution, so it isn't that bad after all.

                          Let us presume that the other 5% is due to differences in thickness between CDs; the other 95% being within margin of the Red Book standards. It is likely that your transport problems are a result of this difference: the clamp assembly just hasn't enough margin to cope with thinner or thicker CDs since it has to have been designed with the Red Book standards in mind. Like you said, this design probably was done overly precise. Transport suspension, laser and spindle assembly etc. don't have much to do with that.

                          I had a TEAC CD transport in the past with more or less the same transport assembly you mentioned, but that had quite a wide gap for the clamp to spin in and it didn't have such problems.

                          I'm afraid there isn't a cut-and-dried solution for your problem, Menschenstimme! You could try and contact the manufacturer of your player to see if there were problems like this in the past. (If it is Meridian: they have an excellent customer helpdesk as far as I know)


                          Sadly: the pitfall of precise design is preciseness.
                          Last edited by sarqoz; 10-26-2010, 05:44 AM.

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                            #14
                            Yes, Sarqoz; it is time to turn this over to the professionals.

                            Thanks again for all of your help!

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