I want to build a 5.1 surround sound system. The main speakers would be a 3-way rather than two-way design for the performance reasons cited in the video here. https://www.axiomaudio.com/m5-bookshelf-speakers

The 5-channel Class AB power amp https://www.crutchfield.com/S-4qWPQyxK7XD/p_313A52PB/Parasound-Halo-A-52.html https://www.stereophile.com/content/music-round-91-parasound-halo-52-page-2 driving those five speakers will feed the unbalanced inputs of a multichannel DAC like this one. https://www.exasound.com/Products/e688-channelDAC.aspx

And the DAC’s balanced inputs would be fed by two pairs of these powered subs https://jamesromeyn.com/speakers/subwoofers/ak-tall-subs/ or two pairs of these powered subs. https://www.rythmikaudio.com/F12SE.html

A standalone or software assisted DSP solution for bass management and room correction will be added later.

Presumably, the problem of classifying the “acoustically relevant” size of my listening room is that its basic dimensions spill over and extend into other rooms. And because it does so-and because there’s probably little that I can do to acoustically correct for this-how much will negatively impact sound quality?

My Listening Room

Width: 11 feet. But it then extends across a ~3.5 ft wide hallway, and which is ~ 14 feet long where the three doors can be closed there.

Then one foot past that hallway my listening room then empties into the kitchen that extends the total width by another 8 ft. And the kitchen length is ~ 10 ft. Then immediately past the kitchen wall the room’s width crosses past a 4 ft. wide L-shaped downstairs staircase, which extends my room’s 11-foot room width by another 11 feet, before turning to go further downstairs.

Windows. My room has three bay windows all on one wall which I usually keep closed and draped.

Length: Just under 20 ft.

Height: Triangular ceiling. Apex 11 ft that declines to 8 ft.

Therefore, given my room’s “effective size” and acoustical environment should I choose five 3-way bookshelf speakers, each placed on a ~20” high platform on the floor?

Or some combination of 3-way bookshelf and 3-way floor standing speakers?