Uni-Protractor Set tonearm alignment

Dear Chris,
my ET 2 was mounted first on the big Le Tallec tt (modified) and later on the Apolyt (450 lbs chassis, 100 lbs composite platter on radial/axial air bearing, 2 Hz air suspension frequency of whole turntable).
The ET 2.5 was mounted on the Apolyt only.
I worked mainly - as far as I recall - with 0.4 to 0.6 bar.
In american psi this means 6 to 8 psi approximately.
This was read down at the Apolyt's control board.
Cheers,
D.

Dear D -
That Apolyt is quite the platter and those arm pods. :)

My extensive testing of the 2.5 showed me that 6-8 working psi is a very safe albeit too LOW psi for the 2.5 to show its stuff. So am not surprised at your earlier remarks.

I found the ET 2.5 starts coming into its own around 16 psi to about 20 psi. My findings were later confirmed by Arthur Salvatore who told me his members recommend 19 psi. "Above 19 psi and the arm starts to lose information".

At 19 psi – the ET 2.5 has phenomenal PRAT, Bass Attack, HF, sounds the most natural. It competes with arms well above its $2900 US purchase price. I very much recommend to those with the ET 2.0 to have them upgraded to the 2.5 bearing along with a Timeter Aridyne medical pump available on Ebay. These two mods make the basic ET 2.0 arm are a giant killer.

Good luck and much success with your Uni D.

Cheers Chris

Dear Chris, I found my old files ... last setting with the ET 2.5 was 1.2 bar. Notes further mentioned "threshold - can't take more pressure due to material and problems with re-bouncing air stream".
Cheers,
D.

Dear Chris, my last post just crossed with your answer - indeed, the bearing of the ET 2.5 can take much higher pressure. I found my tonearm files with the remarks about the ET 2.5 and my last settings were around 1.0 to 1.1 bar - which is, as you mentioned too, about 16/17 psi. Beyond that the re-bouncing airstream and material instability did downgrade the ET 2.5's performance.
Thanks, Chris - the sales on the UNI-Pro exceeded my expectations indeed.
The 2nd production run sold out again.
Cheers,
D.

Dear Dertonarm,

any signs of the UNI-P2S having left the labratory or even production stage. The world is waiting...

best & fun only - Thuchan