Any thoughts on the Holbo deck from Slovenia? It combines an air bearing turntable with a linear tracking tonearm, which also runs on air.
@richardbrand Generally speaking, you want zero slop (play, endfloat, whatever you want to call it) between the surface of the platter and the mount of the cartridge. The engineering problem is very much like that of the steering of car or motorbike, where a little bit of slop can make the vehicle dangerous and unsettling to drive.
Air bearings can work but they have to be done properly to get around this issue of zero slop. Its not a trivial problem!
BTW this is the same reason the plinth of the turntable (which is the thing to which the platter and its bearing are bolted) should be exactly the same thing to which the tonearm is mounted. For example if the arm is mounted to something that is damped better than the mount of the platter bearing, any vibration that the platter bearing might be subjected to can by picked up by the tonearm. To prevent this (to lower noise) the mount of the platter bearing and the mount of the tonearm are the same part.