Originally Posted by SOWK
I have not tried that yet, but would be easy to do if I wanted to just plug in the current wide's (2015 212HT's) into the power amps speaker terminals for the left and right channel.
That would be an interesting test.
I found I had to toe them in more for the imaging to really lock in, but YMMV.
Also, you might run into trouble using room EQ meant for a different speaker and placement, if you don't re-run room EQ. :\
Of course, using the HTRs would be ideal, but the HTs should at least give you an idea of whether you like the wider soundstage without "wide" processing, which IMO detracts from the soundstage.
In fact, I personally dislike any matrix mixing that involves the LCR signals. I feel like they all sacrifice clarity and imaging where it is most critical.
Wide placement doesn't have these problems.
Incidentally, object based audio is also free from needing to do any matrix mixing of LCR signals.