Has anyone added a small subwoofer to 2 channel and been thrilled with the result?


The subwoofer can of worms.
I’d like to add some bass to my otherwise fine 2 speaker setup and have limited space so perhaps a single 10in?
After a few weeks of research the only conclusion I can come up with is - everyone agrees they have to be setup properly. Every brand and technology has their own following and most recommend using 2 (which I don’t want due to space concerns). My room is 12 x 13 ft with box raised ceiling.
After much research, these are the subwoofers I’m trying to pick from, for various reasons:
Rythmik FM8  - lots of hifi fans
JL audio e110 - fantastic support
REL T/9i - sort of a gold standard
KEF R400b - interesting technology, makes me grin. 

I've never heard any of these.
System:
Hegel H160
SF Concerto speakers on stands.
Ben
casteeb
David24 very few speakers rated to 35hz are actually putting out a true 35 hz in the listening position at realistic levels. The measurement is taken at 1 meter at low volume. So good chance a good sub can make a big difference.  It did for me
I've had great success with RELs being added to an already great-sounding system.  I don't listen to loud music so my 2 RELs add a lot of fullness to everything.  But be sure to connect them "speaker" level versus "line level" to get the best results.  That's the way they are designed.  You can't go wrong with REL.
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