The Wonderful World of Turntable Design


#401

Aye, pink in particular


#402

Nice piece about platters & bearings.

http://www.enjoythemusic.com/magazine/manufacture/0208/

If I was in the market for a sub £1000 TT I’d be making Emporium a lowball offer for that Lurne TT with the Xenon & fixing it.


#403

Very interesting.

The run down time on the Motus II seems adequate :wink:


#404

I’d agree in the case of the Motus but I think in some instances a little constant drag can be useful in smoothing out pulses in the motor’s ‘pull’.

That said, the chap behind this device feels that increasing the drag compromises the dynamic range of the TT.

http://www.9tci.com/

It isn’t an experiment I’ve tried.


#405

Didn’t the Cranfield Rock have ‘drag’ via the bearing with a viscous liquid?


#406

Yes although I’m not sure it was ever effectively able to lift its platter/bearing as some suggested it did.


#407

I suppose that’s the key word, although I’m not sure how much additional ‘noise’ the drag would create (and if that noise was audible)

How much drag does a stylus create running in the groove? Is that audible and, if so, how can it be compensated for?

As you can see, I don’t know the answers to these questions :grinning:


#408

Subjective i know, however the “best” sounding bearing i tried in my diy Lenco projects was one with a deliberate drag, a tight tolerance plus a honey type lubricant (a very thick oil). It was the one that also stopped in the smoothest way.


#409

Did you make the bearing or was it a commercial one?


#410

Same q as above


#411

Somewhere inbetween. Was made by a chap who posted on LH. I had an early one, he tried to make a business out of it but failed.


#412

Ah, I remember


#413

As well as stopping in the smoothest way it also had the shortest spin down time. I must have had 6 different bearings in total. I kinda concluded its not how long it takes to stop but how it stops that is important.
Probably bollocks but there you are.

Edit to add. My 1200gr actually spins backwards slightly when it stops which is CRAP. I don’t think its bearing related more likely some sort of magnetic cogging.


#414

The Kronos has an inverted bearing with a single ceramic ball running in an oil bath.


#415

So some sort of non contact, possibly magnetic system for resistance to the motor turning would therefore be ideal? Someone should look into that…


#416

If there was a right way they’d all be doing it.

Physics neans compromises and as he says, throw aesthetics in the pot as well…


#417

#418

I think he was referring to Garrard’s eddy current brake :grinning:


#419

Oops, yes… I should probably learn to read. One day…


#420

typing would be good too :wink: