From Marten Coltrane to Avalon Isis, Hansen King??

I like all the speakers you mention. If I had to choose for my own system I would go with Avalon ISIS of the ones you list.

The ISIS uses some of the technology in midrange and/or tweeter as Marten Coltrane, Kharma Exquisite, Evolution Acoustics and Lumen White.

I like the high frequencies of the Kharma and ISIS the best of the group. The bass of the ISIS Is extraordinary, perhaps the best of the group. Dynamics of the Hansen is excellent but I think the top end is a bit rougher than Marten and certainly more so than Kharma or ISIS.

Hope I'm not confusing you, all these speakers have their own sound and it's difficult to sort out strengths and weaknesses without considering more than just bass performance.

Do you believe the Hansen and Isis will have a larger soundstage then the Marten?

Difficult to say, soundstage is a product of room, speaker placement and even the electronics. I'm one of those that's much more sensitive to tonal balance than imaging or sound stage, but if I had to rate these I would put ISIS on top for sound stage, pretty much matched by Hansen and then followed by Kharma and then Marten.

This last statement is sloppy logic :^), based on listening in various rooms at different times. Perhaps another member will have direct A+B with these, although I think that's a pretty tall order considering price and exclusivity of these lines.