Subwoofer for classical music listener

Schubert: You're right. But right now I'm still in the "audiophile" stage.  When I settle down a bit I'll be "Bach."
But, the audiophile stage is a lot of fun!

tablejockey: I don't know where I'd put a second sub.  The opposite wall from the current sub has a doorway and a closet.
  I'm just enjoying the way it is now.
Maybe later I'll figure something out.

Sunfire True Subwoofer

I just fine tuned the bass of the sub by a method that some people might find useful.  Like, I'm sure, most new subwoofer owners, I had  the bass tuned higher than I should have.  Then I listened to two records of a classical symphony
 ( Mozart's 39th in Eb.)  By finding the balance (equal volume) between upper (violins) and lower strings (cellos and basses,) I got the best quality of sound.
I then tested many other combinations of instruments (including organ) and styles  (including jazz) and found everything to be in balance.

rvpiano-

I too, have the constraints of the system among a living space(no dedicated room)

My 2 sub configuration has BOTH subs equidistant to floorstanders  BEHIND the listening sofa-long walls. 
This pressurizes the room in a convincing manner. Bass envelops the room-but not is an obstrusive way. You end up dialing back the settings, as the subs work less.

As an aesthetic benefit, no unsightly giant boxes behind the floorstanders.
I have them on brass footers/4" maple slabs also brass footers(Mapleshade)

A single sub in my room was fine, but the second eliminated a room mode,also changing the very lowest of bass tones(slightly mushy) to a clearer,defined more convincing presentation. Finding the 2nd sub for cheap was the only reason for even considering the sub. I was happy with the single REL.

As a side note,  the 1812 Overture WITH cannons is glorious. A visceral experience-almost as if you're standing next to them!

Happy listening.

Tablejockey:  When I'm ready, I'll start experimenting with two subs.
I can see I'll have to get creative in setting them up.
It would probably be an improvement over one.
So far, though, I'm delighted with the one I have.

Happy listening to you too!