I put jacks under my speakers which are on a suspended wooden floor. Obviously it significantly stiffens the floor and really improved everything, bass in particular.
I then sat the speakers on vibropods, sat on a granite slab, sat on sorbathane feet. This reduced the transmission into the floor and brought additional benefits.
The new AN arm will be a great match for the IO, if you were in the UK I would suggest looking for an old Voyd 0.5 Ref or Voyd Reference, but I am not sure many made it over to the US.
Enjoy