Two subs or not Two subs?


I have been contemplating adding a Rel T-3 Or two.To my vinyl only 2 channel set up.

Proac responce 2
TAD Hibachi-II Mono Blocks
PS Audio GCPH
Pro-Ject 2 Xperience with an Ortofon HMC 20 cartridge

My room is 20'L x 15'W x 10'H and the speakers are on the short wall.
First are two subs better than one. what are the benefits of having two vs. one. Can I get by with one. Thank You
128x128wilson667
For music, I always use two subs. They image — they reshape the soundstage as it really was. I have a live Jazz recording I use as a reference — for years, with a single sub, bass player was way back in the soundstage, center stage. Adding the second sub, he moved 10 feet to the left. It was more than just one instrument moving — his relationship to other players and their collective energy was more vibrant, and the archictecture of the nightclub became a real place.
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My single REL was never directional, but I added a second one (also costing 200 bucks used), a Q108II…it's all better as the RELs are dissimilar (an 8" down firing, and a 10" forward firing) and complementary.