Always good to hear prospective kit in *your* room

My Isobariks sounded good in my room.

The Aurum Montans a bit better but much better with Coherent speaker cable and Townshend wobbly stands.

TAD a big step up

The FH3 design is a good example of using the room to intentionally extend the cabinet's action, the curved rear horn mouth controlling a reflected wave that grows to give effectively a much larger horn mouth. This lowers the impedance of the transition from speaker to free air, giving large scale and presence. Output at floor level extends low frequency performance and uses room loading much as a sub does. Restricting this part of the speaker's total output is pretty effective at tailoring this design to different room sizes and their character.

I think more could be done with making speakers' adjustable. Of course there's room measurement and DSP to be had, but mechanically switched selection of driver output options for example, might not be too left field. The question of designing speakers for flat anechoic chamber response for a product that will never be used in those conditions is saying "our speaker is neutral, the rest is your problem". Conversely, although I'm sure there is much more to the Allison design, simply reducing the bass output to allow for room gain requires settling on the response of a 'typical' room.

We could always match an amp to a given speaker to match a given room - but imagine how hit and miss that would be!      
   

I went from what was probably a room of the right size to a monster, also rectangle to square.

System certainly took a step down in sound quality.
Improved when I had a ring circuit just for the hifi and a bank of unswitched sockets but still not as good as the previous room

More thoughts on room treatment. I've called my room 'pretty dead' and I believe I like it more dead than I hear in many friends' systems. When I speak in a normal voice in the middle of the room, it sounds much more dead than any other room in the house: there is little echo to give bat-like feedback about the space I'm in. When I clap my hands I get no echo (the room had significant echo when empty) and just a little flutter echo (that 'zzzzing' sound after the main clap).

I've read many times about how the room should be balanced to provide some reflection, and indeed my TubeTraps are tuneable by turning them towards the reflective face or towards the absorptive face as required.  I think these articles were written by classical enthusiasts used to the reverb of a big hall and missing it in some recordings.  For instance, my Israel SO CD of Bernstein conducting the Rites of Spring is a strangely dead, reverb-free recording that doesn't sound natural.  Yet I find myself always tuning for maximum absorption.

I feel differently about my listening room compared with many articles I've read: I simply want my speakers to do ALL the talking, and the room to contribute as little as possible.  I like the resulting sound very much.  Am I different from the norm?

Well, that sounds much like my view.

As I said above, "I want to hear reverb effects if they are on the recording but not if they're added by my own room."

As for matching the speakers with the room size, I've never managed to find a reasonably scientific way to match the two.
Obviuosly multiple trials with different speakers will give you the subjective view, but there must be something better than that.

I've not even found a solid description of what constitutes a small, medium, or large room, nor whether large speakers are a better match for large rooms etc.

I have a feeling that my KEF's (Reference model 3~2) should really be in a larger room than my 4m x 7m x 2.5(ceiling) 

Thanks, all.

Better get back on topic. I'm hoping to get the heating working again soon as the fan heater raises the noise floor somewhat. I'm still very much discovering music that I thought I knew well, sounding completely different in the new room. There is more insight, finer detail and a much better developed soundstage. Bass is far better - I played my favourite Durufle Requiem (the Shaw/Atlanta SO) and I realised how much more easily I can follow all the organ pedal notes. It was the same with the Respighi Pines of Rome (Lane, Atlanta SO), way easier to follow the bass line from the organ.

Where are you intending to put the Gale '401' Speakers & what equipment will you be using with them?

You mean the original Green & Black Diamonds?