News from team trial & error: I second RD's findings in respect of open housings. Just fumbled a bit with EddieE's dull HP1, took the systems out and tried them "naked" with some old MS1 comfies.
WHAT A SOUND !!!!! It's crisp, it's alive, it's detailled, it's musical...and it
May needs some fine tuning with micropore or so to get a bit warmth back, but principally I think these systems desperately need to be Grado'ed!!!!
Edit: Covered 80% of the driver's back surface with micropore, took all other damping away and put them back into the housing. A bit bright, but principally works. But house-less sounds better...