PMC IB1 and room size

No problem. Great speaker. Great choice. Go for the active though (if you can afford it/get it). You don't need to audition reputable speakers like this anyway (I expect you know that you are getting a neutral and dynamic sound...if you like the warm harmonically loaded sound of tubes then STOP...this might be a mistake)

They are very similar in design to ATC's three ways but have an extended bass output (TL design to boost LF) and are less forward sounding in the dome mid range (PMC used ATC dome mids in the past but now use their own dome). I would not hesistate to recommend PMC IB1 even for your small room size, knowing that it is not square.

I'd recommend a PEQ to tame the bass below 60 Hz, as it is hard to achieve much with acoustic treatments at such very low frequencies. The PMC may well need taming in your room as they have significant LF output. A great speaker!

Oh yes -- I want them for their clinical, revealing, painful-when-the-recording-sucks presentation. ;)

I'll have to listen to lots of reference recordings to get a sense for how the bass is playing out in the room. I really only need it to sound right at listening position.

Not going active, as I have a Bryston 4BST, which I've been told is an ideal mate.

Thanks for the info!
Carl

any room is cool

Carl:

I have a pair of IB1's and an IB1 center in a room of the same size as yours and they are fantastic speakers. Mine are against the wall with no problems. When you are ready, the 4B-SST is a huge improvement over the 4B-ST with the IB1s.

How would you characterize the improvement moving from ST to SST?