This is coming from a nut case who has 9 subs...4 each are 15" (long story behind that, but glad it all came to be). It most definitely makes a difference. It's like driving a V-12 versus a 4 cylinder. You can climb a steep mountain pass at the same speed driving both cars, but the 4 cylinder will be screaming in a lower gear, while the V-12 is barely breaking a sweat...cruising all the way.
It's the same with subs in my opinion. Them 9 subs just cruise at the same level as a single sub, but it cruises right through you. Or if desired, at nearly all the live performances I have been to, the bass is rocking the place...you can take that route too.
I was terminated and made obsolete by Mrs. LB-V the first time I let them all rip. She was silent for several days.
Anyway, I digressed way off topic...couldn't resist.
For Black Friday I bought some string lights for my backyard.
Edit:
@GOS, definitely NEED.