Turntable Bearings


How can we tell the condition of a used TT bearing with a good and reasonable accuracy other than just observing it?
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The new(er) bearings will fit in the older tables. There are literally thousands of 30 year old LP12 in service with their original bearings and existing owners are not complaining. If you like the Linn sound, an older LP 12 with an Ittok arm in for around the $1k range used is hard to beat.

Btw, you can always purchase a cheap digital USB microscope and check for a flat spot on the spindle point.
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Microscope! That's the ticket. To address OCD;I agree to some extent; I know it appears a little overzealous to question the bbearing condition like this. But let me say this. I stated earlier that the bass sound seemed to be more diffuse and not quite as sharp and detailed as it was initially. How do I know? My only defense is I hhave owned the table for 30 yrs. I like to listen. If I felt I could not seriously tell these things then I would take up golf and buy a BOse system. But I trust my ears and this is my hobby and if you can't do that then whats the point? Please not to sound harsh it's just how I feel.
To answer your question, one must first determine the value of the table in what you believe it's current condition to be. I sounds as if you are somewhat confident that there is/could be an issue with the bearing. At this point, walk away there are many many of these LP12's in various states of condition and upgrade on the market. You can buy a LP12 from a dealer as mentioned for as low as 2000.00 that he would have gone thru. I know Rick would not let a "problem prone" TT out of his shop. He may and will suggest upgrades as that is a dealers path of business to LP12 owners. As far as what will fit the oldest LP12, anything Linn produces will retro fit their LP12's. They never have changed the base units, just keep adding upgrades,e.g. motors, bearings, suspension, arm boards, tonearms, power supply's and the list goes on. As a former owner I decided to move in another direction as the desire to upgrade would have been too expensive. But with out know what dollar figure you are looking at on this particular LP12, it is hard to justify if you have to turn around and spend 1300.00 right away. If you could buy a ready to go and properly tuned table for 2000-2500.00 I know where I start.
All my opinion of course. But from what I am reading, you seem very concerned about this table's bearing and, I have found my fears/concerns are usually warranted. If you are hearing something that doesn't sound right, it probably isn't and LP12's are a expensive when trial and error trouble shooting them.
Again just my opinion and no intent of offensive content.
When was the last time you had your 30 year old LP12 serviced or tuned? That would have a MUCH greater impact on the sound than bearing wear. Perhaps, time for new springs, grommets, and a suspension adjustment.