Upgrade from TW Acustic Raven AC-3 to what?

Dear Dertonarm,
I see your point very well, if someone will invest the money i´d rather like watching the race between active and passive isolation by myself - just for interest.The question remains if it is worth the investment. Nevertheless you also know the famous words: no risk no fun...
or: believe what you hear
or: trust your good friends

Dear Thuchan, see whenever possible I look for the option which does involve the least periphery and as few parts which can actually fail. Thus bringing the meantime before failure as well as the percentage of possible failure to the minimum possible.
All this of course with equal performance. In this particular matter it all comes down to low resonance frequency and high damping - no matter whether active or passive.

"We will never see a lightweight TT nor an unsuspended one, with a platter less than 30-50 lbs coming anywhere near the point of closing the book on TT nor approaching its true frontiers.
As we all will see - as they will come and go in half years turn.
The same they have done so for the past 40+ years in high-end."
You misread my comments - my turntable is the Final Audio Parthenon - 25kg+ platter, massive bearing and composite gunmetal rigid plinth and armboards, along with massive motor using power regeneration and power amp for the motor. If you do a search on the net you will find that the top brinkmann's etc are still catching up to my turntable which was built in the 70's. Final used to "upgrade" the big micro's as well as build their own turntable. I dont like the SP10 mkiii just said it was the best dd I've heard. And yes I've had the air bearing tables, arms and moved on. I seem to be sensitive to speed stability, timing and compression - dont want a rose tinted front end with timing issues.

I am familiar with the Final audio products - and with the Parthenon.
As for "timing" and speed control. My table runs with the big Studer Capstan motor with regulation and Studer speed control. This was good enough for the majority of the music recorded from the 1960ies to late 1990ies. So the stability of the "timing" on most of your records was determined by this very motor drive and its control board. I always found this a most suitable solution.
Especially so as it makes all other TT-motors look like lightweight dwarfs.

As for air-bearings ... well, there are air-bearings out there quite different to the ones "usually" seen in high-end audio. Its all a matter of "thinking in different scales".
And - its not just you being "sensitive to speed stability". Everyone with a remote interest in piano music will gladly join in.

Dover, what are the specifics of the motor and speed control? Low or high torque? AC or DC?