I had the same question.
I took my 20 yo home theater sub (B&W ASW1000 which is just fine for move explosions and helicopters) and hooked it up to my dedicated 2 channel system, just to see what it sounded like with my B&W 805D3s, not expecting much. I dialed the crossover down to maybe 50Hz, set the volume to just under where it was obvious, and immediately heard the difference. Even that old tubby/slow HT sub added a depth and warmth that wasn't there before. Whole experiment took maybe 30 minutes.
After proving the value to myself, I got 2 REL S510s and took the time to place them and dial them in. Night and Day. Shocking, really.
If you don't have an old sub laying around, borrow one from a friend or you can probably find a used one on craigslist for super cheap. It doesn't have to be very good or modern to do your own experiment.
I took my 20 yo home theater sub (B&W ASW1000 which is just fine for move explosions and helicopters) and hooked it up to my dedicated 2 channel system, just to see what it sounded like with my B&W 805D3s, not expecting much. I dialed the crossover down to maybe 50Hz, set the volume to just under where it was obvious, and immediately heard the difference. Even that old tubby/slow HT sub added a depth and warmth that wasn't there before. Whole experiment took maybe 30 minutes.
After proving the value to myself, I got 2 REL S510s and took the time to place them and dial them in. Night and Day. Shocking, really.
If you don't have an old sub laying around, borrow one from a friend or you can probably find a used one on craigslist for super cheap. It doesn't have to be very good or modern to do your own experiment.