Hi David: For about $20 or so you can make considerable sonic improvements to the player. You are on the right track with damping. Go to Home Depot or similar and buy the industrial linoleum floor tile (about 80 cents for a 12 x 12 or so piece, you might need 3 or 4 pieces) and some heavy duty double sided carpet tape. Skip the peel and stick stuff, the non-adhesive heavy duty linoleum (about 3/16th of an inch thick) is much heavier and much more inert-it will do a fabulous job-you'll need an exacto or drywall knife to cut it. I have done both the interior and exterior of a couple of players with very good results. You can choose a lighter or darker colour to match the player-will look a little funky if you do the exterior, but if performance is what you're after do it all. While you're at the Depot, spend another few bucks on rope caulk (this is window caulk which is in long gray or white strips which you simply tear off) and apply it everywhere you can on the top and sides of the transport mechanism taking care that you don't interfere with any moving parts. Easiest way to establish what's moving is to plug the player in after you've taken the top off and open and close the tray. Obviously, you don't want to cover the round central disc in the centre of the transport which rotates and to which the CD is clamped. The underside of the tray is tougher-I wouldn't use the rope caulk there is it may fall off. I used some Marine Silicone on the last player I was using, as it will dry well and stay in place-I'm not really sure that this made much of a difference, and wouldn't be overly concerned about doing the tray.
I'd also rope caulk the player's crystal, which should look like a little metal tin can on the board with all the capacitors and chips etc. Cover it with rope caulk and use a toothpick to push the caulk down toward the circuit board (I've gone close to but not touching the circuit board).
If you don't want to perform major power cord surgery, simply hack off the molded plug and replace it with a cryoed Marinco 5266 (about $7-$8 U.S. from Take Five Audio-probably more at other places but maybe less to ship if you are in the U.S.) This alone will give you a nice solid improvement in high and low frequency response and a smoother presentation.
I'd continue to use the sorbothane feet and probably also sandbag (using the large zip lock bags) the top of the player as well.
Do all this and it'll probably sound better than the 555.
I'd also rope caulk the player's crystal, which should look like a little metal tin can on the board with all the capacitors and chips etc. Cover it with rope caulk and use a toothpick to push the caulk down toward the circuit board (I've gone close to but not touching the circuit board).
If you don't want to perform major power cord surgery, simply hack off the molded plug and replace it with a cryoed Marinco 5266 (about $7-$8 U.S. from Take Five Audio-probably more at other places but maybe less to ship if you are in the U.S.) This alone will give you a nice solid improvement in high and low frequency response and a smoother presentation.
I'd continue to use the sorbothane feet and probably also sandbag (using the large zip lock bags) the top of the player as well.
Do all this and it'll probably sound better than the 555.