Hi, new to this forum. Beginning a search for hieff speakers to match 300B SET. Want to consider room interaction/reflection issues given that the speakers sit within an alcove and radiate toward the larger living room (see attached pic). An 18" ceiling beam divides the ceilings between these two areas of the room (as well as wall that extends 3' into room at top of pic), creating a "chamber" within which the speakers sit.

Would corner horns along left-most wall work well in this room or not? What speaker designs (narrow radiation designs, front or back horn, MLTL, sealed sub w/ dipole mids, etc.) would perform WELL in this room? It would also be helpful to identify designs that I should AVOID due to poor room interaction. Thanks for input!

31,7Hz - Width(30.2), Length(32.7)
63,5Hz - Height(66.5), Width(60.4), Length(65.3)
127Hz - bis(132.9), (120.9), (130.6)

Solutions to adress this problem are (as an ex.)1. change room dimensions (not all of them at the-same-time/the-same-way but make one bigger the other smaller or maintain one and change the other), 2. acoustically treat the room, and/or 3. equalize (slide down these freqs to have some control on them - i.e. reverberation or resonance)
(S.Shenefield 1997)

1. Read post on another board in which the Pi customer stated that you suggest at least 6 feet clear on each side of the cornerhorn. While viewing the schematic of my room above, please note that I have one corner (upper left) that runs only 5 1/2 feet before terminating into a wall that extends 32" into the room. I'm sooo clooose...but this was my initial concern. Still OK?

2. The cab dimensions appear the same for 7 series beggining with Stage through Pro. Assume there's an upgrade path here Theater appear larger. I've observed that a LOT of SET guys own Theater 4's. Are the Theater 7's the series of choice for SET users? Would be good to start with Stage or Premium to preserve upgrade path to Pros in the future.

Priorities are inner resolution, coherence, tonal balance, dynamic contrast at medium volume over say ultra high SPL.

Thanks for any feedback!

As for models, the Professional Series seven π's are definitely the best. The Stage model is good, great bang for the buck. The Theater is nice too, but large. Makes the bass bin as wide as the midhorn. All are fine with SET amps because the impedance curve is very smooth. The midhorn and woofer tend to damp each other and smooth the overall impedance curve.