A Copernican View of the Turntable System

Dear Dgob – Looking forward to your impressions of how the sound changes when you isolate the armboard. I did not see any value myself in attaching an armboard to a surface containing a motor and vibrations so I went directly to an isolated armboard. If the improvement that you noted was based on this alone - I can’t imagine how much better? your next step will bring. It also speaks volumes to the top end component that an sp10 is.
I really believe the SP10 engineers didn’t realize how good they made it. Think about it – they didn’t know what type of structure alias plinth - the broadcast studios were going to put them in - so they made them “bullet proof” to work great without a plinth anywhere. They had to - they wouldn’t have become the standard worldwide if this was not the case. Conventional wisdom said put it in a plinth so they made plinths for it as well to sell. This is the same reason I started with a plinth - go with the flow. It took a lot of courage Raul to keep up the front on your side. Henry it was your thread with the pictures that got me going. Kudos to both of you. I am listening tonight and I can’t believe the sound.

I have a seasonal summer cottage in the woods. This whole thing is starting to remind me of catching mice except in a good way here. For every mouse that you catch there are ten-fold and more lurking somewhere else in the structure. As we speak there are probably “x00’s” maybe "x000's" of folks trying this out as Raul has referenced. If the thought of this is forcing some folks to cringe and hide or talks words around it so be it. My SP10 and ET arm hasn’t fallen over yet. Hearing is believing as Dgob said. Something tells me they are all trying or planning on trying it too really soon - they just are not saying anything ………yet :) This is just too big a deal for us turntable people to ignore or talk words to.

Cheers Chris

Dear Chris,
Thanks for the kind words and yes....kudos to Raul for planting the idea for the 'Nude Turntable' in my head.

You may be right about lots of other people now trying out the same experiment as my Thread is recording an average of 100 hits every day despite the fact that it doesn't appear on this site and they have to go searching for it??!!

Hopefully some of these 'experimenters' will eventually contribute their thoughts in this Forum?

Knowledge is free.

Halcro,
Regarding your last post of 1/27, I think the 'theoretical proof' that Ralph offered earlier in the thread more than covers the issue regarding the desirability of having the tonearm mount absolutely stable in space vis-a-vis the turntable platter axis/level. Any movement between the two will show up as distortion. There is no getting around that.

If I were going to decide to 'go nude' with an outboard tonearm pod... I would...
1) build a tonearm pod (or three) like yours - I think it is a great design - VERY heavy with threaded bottom allowing one to spike it to a platform,
2) mount the nude TT to the same platform that the tonearm pod was mounted to, probably using the same spikes as on the tonearm pod,
3) I would put pneumatic footers, if any, between the 'platform' and whatever it was mounted on.

Banquo,
As regards putting 'light' objects on pneumatic footers with very large weight limits... I think the value of using pneumatic footers is to reduce the resonance frequency of the mounting to as low as one can in both the horizontal and the vertical. If one mounts a 10kg object onto 3 footers which can EACH carry 10-20kg, I expect that would be a problem. I have found when I have used platforms and pneumatic/magnetic isolators that it is always better to be at the heavy end of the range rather than the light end.

Dear Banquo - I forgot to ask in my last post how you are making out with the repairs on your sp10 ?

Also - maybe one of the members here can hook u up with a plinth to try to compare with your current setup ?

T_bone is absolutely right - any damping (pneumatic, oil-based, elastomer - whatever) will only reach its optimum read: lowest possible) resonance frequency and spec behavior at its maximum load.
So here for once any over-compensation regarding parts is not just futile but entirely contra-productive.
That's why even most high-priced isolation platforms do need additional load in addition to audio components resting on them to really "work" the way the are designed for.
Same regarding the other points in T_bone's post. They are correct and describe the correct way to handle the topic if going for a TT without "classical plinth".
Cheers,
D.
post scriptum: I wonder why this thread has to be searched for and isn't available anymore through the Analog Forum's front page ... any idea anybody ?