I used to run a Furman IT 1220, (balanced power similar to EqiTech) then a Hydra 2, then power amps,but never tried putting the Hydra in front of the Furman.
In my mind it seemed more correct to balance the power and then filter it.
Also,the Furman has a huge transformer so I felt that I would be limiting it somehow by running it into the Hydra first and not the wall.
Some folks think that power amps with large transformers are robbed when they aren't wall plugged so plugging the Furman into the wall seemed to make sense to me.
I did have a friend ask me why I didn't do it the other way around, but I've since changed systems and power my amps direct from the panel using 20 amp breaker and two runs of solid Romex # 10, with no isolation transformer or power conditioner,but using high quality receptacles from the same manufaturere and using the same material construction.
Until I powered up this way,using the Furman and Hydra on a non dedicated standard line was better than into the wall without either.