Definitely stereo. I too did this years back using my Kenwood 9600 receiver (still have it and it still sounds great) and two sets of Bose speakers -- an old pair of 301's & what I think were the first version of Acoustimass® speakers (no longer available). The 301's were near the TV, the Acoustimass sub-woofer sat in a corner and the Acoustimass treble set did their direct-reflecting thing -- great all-around sound.

But what does this have to do with the idiocy of Pokémon Go other than dating us as too old to understand the idiocy LOL (pronounced Loll)...