Eminent Technology ET-2 Tonearm Owners

I think too, that the smaller ET2  alu tubewill fit that cartridge nicely, specially when it's the high pressure model.
My B&O MMC2 OTOH works very well too even with the heavier ET 2.5  manifold/tube and the magnesium arm tube - the arm is quite tolerant if you are careful with the counterweight springs, damping etc.
The WISA pump was not original, it came with the tank as a third party ET2 "tweak". The WISA pump (at least mine) delivered less pressure and more pulses - it is a single membrane pump. And yes the 50 Hz pulses subtly "made something with the bass" - ie. more prominences in that range but not an increase of transparency...
The original pump was (is?) a rel. low noise Takatsuki double membrane pump.
Adding the surge tank is an audible and easy improvement.
In my setup increasing the pressure is improving the sound considerably up to ca. 0.5 Bar above which I found it difficult to hear as an improvement.
There is an increase of turbulent air exiting the manifold with increasing pressure, it might be a sort of trade-off of increasing bearing "stiffness" vs. air noise.
 

I stand corrected.  I do have the Takatsuki app6ga which only has the model number and no manufacturer.  I always thought it was by Wisa.  I finally got the Jun  Air pump working (actually my version is by Werther international, P15-TC1) and it works well but it cycles and produces a loud POP as it switches. I will try a slow start module and see if that helps. If that fails I may need to set up a large tank and either leave it on or suffer the wait each time I go to use it.  It is pretty quiet but I may yet move it out of the room. 

Next step is to re plumb the air supply and include a surge tank. Not expecting much, if any gain, as the compressor already has a small tank.

@pegasus 

I have used the ET2 &vET2.5 with a variety of cartridges including high compliance with no issues. A little tip - you can add eddy brake damping to the lateral arm motion for high compliance cartridges by placing a little cupboard door magnet under the spindle on the opposite side of the air bearing from the cartridge. This actually works, you will be surprised, when I first tried it I actually got an increase in volume, presumably because the cartridge is more stable and focussed. Dynavector uses this same principle with their Dynavector arms - if you look at the back end of a Dynavector arm you will see an arc plate sitting between a pair of magnets - as the arm moves the plate moving across the magnets creates eddy damping of the motion.

With my cartridge having a compliance of 15x10(-6) I don't think I need the magnet but I may try it just to eliminate the approach.  How do I pick a magnet of the proper strength? 

I think I need to rebuild my P15TC pump as it can't quite keep up at 20psi.  According to ET the small diameter high pressure manifold should consume about 2-3 liters a minute and the pump should be able to supply 5-6 LPM at 20 psi.  It also pumps a large amount of oil.  Perhaps I now know why I was able to purchase this $1400 dollar pump for $140.  I Can live with it for now but suspect not after adding a bleed valve which is on the way.  I fully suspect parts are available and not extremely expensive.  More research needed. 

I don't think I need the magnet but I may try it just to eliminate the approach.  How do I pick a magnet of the proper strength? 

I used something like this -

https://www.bunnings.co.nz/handee-white-heavy-duty-magnetic-cupboard-door-catch_p0280054?store=9502&gclsrc=aw.ds&gad_source=1&gad_campaignid=15792554575&gbraid=0AAAAADL7rPqB15ds9Db-4KgOR---oU_Zw&gclid=EAIaIQobChMI5JnK39LzjwMV-NsWBR3Z0yJ8EAQYASABEgL3_vD_BwE

placed on its side with the 2 edges of the magnets running parallel to the spindle just below.