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Should the platter and plinth be level?

Greetings all -

I've always made sure the plinth on my Rega P5 is level using a carpenters "bulls-eye" level. On a whim the other day I popped the level up onto to the platter and was amazed that it did not show it to be level. When I move it down to the plinth - it's showing level.

Don't misunderstand me - it's not a dramatic amount and if I eye-ball the platter and subplatter in relation to the plinth it all looks to be fairly level.

Should I be concerned that the platter is not rotating exactly level to the plinth? Should I adjust everything so that the platter is level and not worry about the plinth being level? I've checked speed, etc. - and everything's working smoothly without any problems so I suppose I shouldn't be worried about it but can't help thinking it's a bit odd.

Any input would be appreciated - I'd also REALLY appreciate anyone owning a P5 or P25 if they wouldn't mind checking to see if the same anomoly exists on their tables - maybe it's just the way it's designed and assembled.
slate1
sdcampbell
2,136 posts
 
It's possible that the well in which the platter shaft and bearing are located is not perfectly vertical, which would make the cause the platter surface to be out of parallel with the plinth. In the situation you describe, it's more important that the platter surface be level than the plinth, since the tonearm and cartridge need to be level for the stylus to track with equal pressure on both sides of the record's grooves. However, if there is much misalignment between the plinth and the platter, I recommend that you take the turntable to a dealer that has experience with turntable setup and ask for an adjustment.
dr_balance
16 posts
 
My P3 did the same thing. I always made sure the platter was level. I did this because that is what the record and arm wil be sitting on.

Cheers,
Balance
raquel
841 posts
 
You need to level the platter, not plinth, for the reason given by Sdcampbell.
slate1 OP
82 posts
 
Thanks everyone - glad to know it's not just mine and I'll re-adjust so the platter is level.
slate1 OP
82 posts
 
Okay - the more I'm thinking about this, the less this is making sense. Adjusting the pitch of the platter by changing the base that it's sitting on isn't going to do anything.

The ONLY element I have control over here is plinth. No matter how I adjust it, the relationship between the tonearm and the platter is going to remain the same because they are both mounted to the plinth. Adjusting the plinth out of level so the platter is level isn't going to change that.

The degree of error here isnt much and it's not in the plane that the tonearm moves across the record in - it's parallell to the tonearm tube. In other words, it's not like the needle is tracking "uphill" or "downhill" - hope that makes sense!

The more I think about it, the only thing this could potentially slightly affect would be VTA and even that would be negligible here especially since I'm using the Rega Exact cartridge.

This is all very interesting, especially since there's another Rega owner with the same issue. I'm beginning to wonder if it's another one of Rega's unusual design elements; although I can't imagine why they would do this. If anyone else has a Rega table and is willing to check - I'd be curious to see if they're all like this!
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