denon DP60L


I have a denon DP60L with a straight tone arm and grado gold cartridge. The arm won't pivot vertically. If I move it manually 1" above the platter it stays there. Same at the platter or tilted to the peak. Any suggestions?

I have it rigged with a Mac 4100 receiver and monitor audio studio 6 bookshelfs. Any suggestions for tube amps and pre-amps to join it with?
128x128cjeharnish
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thanks elizabeth,
unfortunately, the lift is all the way down. the arm can be lifted by hand, but stays in whatever position one sets it to. I thought perhaps the screws at the pivot point were too tight (the slotted screw-in-a-screw connection) but cannot seem to adjust those at all.

i have a theory which is don't break anything you can't fix. I'm approaching that point.

Thanks.
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you are a champ! I'll give it a try in the next few days and let you know my results. Thanks so much, I look forward to unloaded the old B&O and stepping into the denon.

Thanks again.

Chris