That’s a good placement for surround speakers - the BL3’s will be great there.
Since I am an advocate for having the same speakers all the way ‘round, I’d prefer a set of BL3’s for the front, too.
However, the BL8000 will do fine there!
What you should have much focus on, is the olacement of the BL2 in the room.
Subwoofers are generally hard to place in the room - and a BL2 maybe even more.
Do try out several different places for it before you settle and do some cable management.
It might seem like a lot of work, but in the end you might find a better place, than just by placing it ‘somewhere’.
Trial and error....or success is the golden rule with subwoofer placement.
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