Linear tracking turntables, whatever happened?

Uber waltz, I know what you mean.
Even Arthur Salvatore switched back to pivoted arms as his ultimate preference when he felt they had improved enough. ;)

I will chime in with the problem with straight line tracking air bearing arms is definitely the pump and all parts of the air supply leading to the TT.  I had a Maplenoll Ariadne air bearing TT/arm combo for 12 years that was absolutely the best sounding somewhat reasonably priced combo ever built.   The problem is it needed very clean 40 PSI pressure to make the arm bearing work.  The TT would be fine with about 5 PSI.  They had a splitter near the TT that would channel the air to both TT and arm in separate tubes.  There needed to be a governor on that splitter that would divert say 85%of the air to the arm and only 15% to the TT.  If that had been done, who knows just how great the 'Noll might have been.  However, in addition to an extremely loud pump that needed isolation from the room you listen in, I really couldn't run for 4 hours without having overheating problems and either shutting down permanently or rupturing the diaphragm that allows it to pump air.  It also required a filter to clean the air, an air plenum to take the condensing water out of the line caused by the high powered pump--and all these things need a separate aquarium tube to run to each piece from the other.  The setup did not get out of alignment as long as it was leveled and not moved.  GOOD!  The air supply to the TT/arm could be stopped by any of the parts of the air supply delivery crapping out or any of the hose connections popping free from the pressure.  VERY BAD.  Solved that after the first time it happened that way putting on of the small plastic locking straps snugged good over the tube at each connection.

I also have a Trans-Fi Terminator with all the upgrades and it is able to run off a small aquarium pump--solves the 4 hour problem, the arm design only needed 3 PSI; and the noise--very little there.  I used it with a super Lenco rebuild using most of Jean Nantais' upgrades and mods and a giant 100 lb. 10-layered plinth.  The sound is very good, but not as good as the WORKING 'Noll.  A lot safer on the cantilevers of cartridge as there is virtually NO way for the air supply to stop and the arm can float for several minutes IF it did somehow.  It's one problem is a PITA in that the arm is a very short 3" for better sound, BUT...the sliderule like rail the arm floats on actually sits above the record and covers the rear 2" of it with only about an inch of clearance from the record.  You have to lift the record at an angle to take off the record and the same angle to put it on--not a big deal.  But because of its design, when you use the cueing lever, the long thin rod that holds the counterweights ends up rubbing on the record's outside edge too often.  

I ended up buying a very good used pivoting arm that sounds as good or better with the Lenco as the 'Noll.  I LOVE it--the Pete Riggle Woody.  The combo is clearer, more dynamic, and I love it adjustability and easy of use, as in NO issues of any type.  As has been already mentioned, it also looks great.  Probably more than you wanted to know, but I have some experience with both types of arms in a really good system.

Bob

Clearaudio has these offerings.I am still saving for the TT5

https://clearaudio.de/en/products/tonearms-tt5.php https://clearaudio.de/en/products/tonearms-tt3.phphttps://clearaudio.de/en/products/tonearms-tt2.php