New house, new amp, and speaker options (Harbeth, Maggies, GMA or...?)

Hi guys,

I've built a few nice systems over the years. Nothing especially expensive, but some very pleasing, synergistic components.

My most recent system was developed for a small, less than ideal listening space in my home in Lisbon. It consisted of an excellent, re-capped Accuphase E-303x integrated amp, Harbeth P3ESR speakers, and a near-20 year-old Electrocompaniet EMC-1UP CD player.

My new home will include a much larger, though oddly dimensioned listening space. It's not easy to describe clearly, but the floor space is a rectangular ~26 sq. meters. The oddities are that there is an overhang from the floor above, extending out about two meters over one (long) end of the room, and, outside of that overhang, the space above extends all the way up to a V-shaped roof. odd and largely asymmetrical space.

I plan to place the speakers roughly midway along a long side of the room, and the left channel will sit very close to (i.e. below the outer edge of) the above-mentioned overhang.

Note that after extensive research, I have just purchased a Hegel H160 amp, which I expect will be sufficient to power some, if not most of the speakers that are currently on my radar. Those include a rather esoteric pair that I already own, but which have been in storage for the past several years. They are Green Mountain Audio Callistos* (RIP Roy), which I used in NY with a Jeff Rowland Concentra, and liked very much. They were used in a small space, though, and I suspect that they wouldn't be nearly as effective in this larger space.

More likely are a bigger Harbeth model, or Magnepan. Long ago I owned a pair of Tympani III, and they were sensational. I do like the Maggie sound, and am not concerned about some base shyness, but I haven't really listened to any of their more contemporary offerings, so would appreciate some feedback, including optimum distances from the rear wall.

With regard to the Harbeths, I suppose that the C7ES3, SH5+, and M30.1 are all in the mix. I have been very happy with the P3ESR, and do like the Harbeth sound.

I am certainly open to other suggestions, but take into account that I only buy used, would likely spend a maximum of ~$3k, and, as I am based in Europe, options such as Spatial aren't likely to work.

Thanks in advance for any thoughts or insights!

Tony C.

*the GMAs were/are matched with a rare set of – dare I say? – cult classic Osiris stands. Members who have been around long enough may recall the interesting story behind them. In any case, they really are superb, and I would be happy to employ them, if possible, with my next set of speakers, though they would necessarily have to be on the smaller side.
I own and love speakers that conform to the BBC design philosophy (Harbeth, Spendor, Stirling) and recently bought a pair of Magnepan .7s. With a decently powerful amp (like your Hegel), these Maggies offer the best value of any speaker I've encountered, especially at U.S. prices. The .7s actually produce more bass than most speakers the size of C7ES3s. 

I've also owned the Maggie 1.7is but didn't like them nearly as much. The .7 is better balanced, with superior cohesion and bass dynamics. Anyhow, if you like the Harbeth sound, I think you'll find acclimatizing to the .7s is easy. Caveats being that they need at least one meter of distance from the wall behind them, the toe-in can make or break their treble balance and their soundstage imaging  won't be as "pin-point" as that of your P3ESRs, but they're still better in that regard than the larger Maggies. 
Hands down to fill a large room like that will be Emerald Physics 2.8s.
Open Baffle, 2 15" carbon woofers and one 12" concentric midrange per speaker ~ 96dB. MSRP is $9999, BUT, they have a moving special where you can buy HALF OFF, and I think DELIVERED