Over sensitive CD-Player (Denon Ar-1550)

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I'll keep it short, my CD-player has become very sensitive to vibrations and though placing it on a air cushion helped a bit, it's still to jumpy for my taste. I have the service manual and i've checked the mecanical suspension of the lens but I see no fault. What can it be?

Any suggestions are most welcome...

//Greetings from Sweden

Ps. I've tried to run the "service program" but I dont have a reference CD. With a normal CD I get values within the specified limits though.
Hm. A lot of these laser mechanisms use a servo focus system to keep the data track reading properly as disc imperfections and warps etc go by... it could be that the servo adjustments have some somehow gotten out of whack. I'm not a loader expert by any means, but a recalibration of the servo trimpots may be in order - probably not an easy thing for the DIYer though... In a worst-case scenario, the actuators are just worn out, and there's probably not much to be done about that.

You might be able to find information related specifically to the loader. Often times, many different companies will manufacture CD or DVD players using the same loader supplied by one company. If you can't find the necessary information about that specific loader, you might be able to find a used (hopefully cheap) player with the same loader in it, and just swap it out.

I know it's probably not what you want to hear, but from my experience, these things tend to be rather finicky... they're generally reliable, but when something goes wrong, they're just kaput.

Good luck with it.
Hello Anelar,

like hifiZen said it´s probably the focus system that needs calibration.
I now it sounds funny but if you don´t have a service manual and the right equipment it´s possible to do the calibration by ear:eek:

Just open the player (clean the lens) and look for some small trimmers labeled "focus" or "laser" near the loader(usually 2 ). Mark the position they´re in and put a critical cd in the player.
Now you´ll hear the focus system working (clicking sound) and you´ll see if the disc plays without any faults. Now slowly turn one of the trimmers and hear what happens. The clicking noise can get louder (not good) or less (good). If nothing happens put it back to the original position and try the other one. Try trimming so the noise gets as silent as possible and the sensitivity for disturbances gets less.
I know this method isn´t very scientific but it has worked a lot of times with different players.

The last time the tracking system went out of whack with my CD player was when the laser diode was on its dying throes (ie failing!). Admittedly, that particular CD player was already 5 years old at that time, used at least 3 hours daily. Before the laser failed, you can practically slap it hard on the top of the casing without mistracking! Maybe this information could help......

The pickup is probably bad and needs replacement. Denon also players used to have a problem with the rubber suspension groumets failing due to old age.
If the unit uses a Sony pickup the lens suspension could have failed (the lens will be sitting lower in the pickup).
Before adjustment check the PLL frequency is ok. If so try adjusting the focus offset and see what happens. I would not touch any of the other pots unless you have the service manual and the required test equipment.

Thank you...

Thank you for your help, Iv'e checked the suspension and it seems fine to me. The servo adjustement can't be done by hand in my player (Seems automatic) so I guess it's the laser that is on it's way to give up. I'll try to get my hands on a replacement..

Thanks a lot!
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