Spindle oil

El, I'm not familiar with your table but once had a Technics linear table with direct drive and a motor driven linear arm. They were all the rage back in the early eighties but fell out of favor with the high end crowd after proponents of belt drive platters and conventional pivoted arms convinced us that the former were inferior because the direct drive motor was always searching for the proper speed and the arm was crab walking across the record. Maybe it's true and maybe not, but as far as I know they did disappear from the market.

I do believe the best linear arms are capable of better peformance than the best pivoted arms. If they could just get the cost down to where I could afford one. In my price range I think the pivoted arms are superior but I'm not sure what all is out there in the linear world. Everything I see is in the $10,000 plus range.

"On top of that, there's no circulation system involved, so flow time isn't a concern." Not so for all TTs. Sean, you haven't considered the bearing design used by Tom Fletcher in his Nott. TTs. This design does 'pump' oil around the bearing sleeve.

John: Thanks for making me aware of that fact as i was not aware of it.

Herman: High quality linear tracking arms aren't that expensive. That is if you don't mind buying used, can shop around on the net and move fast once you find one. Sean
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Herman..."Crab walking"? I'm not sure what you mean. The Sony PS X-800 arm actually does have a pivot. However, the arm angle is constantly measured, (Hall effect sensors) and the pivot point is moved as necessary to keep this angle tiny. The pivot movement is biased to match the nominal LP groove spacing. Only if the groove spacing changes from nominal does an arm angle develop, and the pivot movement speed varied so as to get the arm angle back to zero (plus or minus 0.05 degrees). At all times the arm is free to pivot, so the servo activity is not seen by the pickup.

Bottom line is that it works flawlessly, and the biotracer vertical servo (not on all Sony linear tracking TT) will handle warped records that would be unplayable on most systems. Another nice feature of the biotracer arm is that the VTF is applied as a bias to the servo, and can be adjusted WHILE a record is playing, so that sonic effects of VTF can be evaluated.

El: I think that Herman meant that the servo controlled linear arm would be cogging side to side ( crab-walking ) trying to constantly correct for the center of the groove. Sean
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