Yes, I probably should have tried that John, but I got impatient to put the Ittok back on. I immediately felt that it brought a greater stability to proceedings, but then I realised the deck still needed proper adjustments, since tracking wasn't perfect. I've got it sounding very good now. I think the next step is to get Johnnie's wiring n the Ittok to get this deck to the place where I really want it.
The 401/AO RB250/Grado Plat Ref is enjoyable in a different way to my LP12. The 401 is very broad and expansive, whilst the LP12 is more muscular, concentrated and purposeful: the central voice has a better focus and consistency with the LP12, whereas there is a more relaxed and open sound with the 401.
I'll begin to work out how much of this is down to cartridge and arm in the coming weeks.