Go for twins, it is a worthwhile step up.
They say bass is unidirectional, but you can hear and feel it emanating from one side unless you run two in stereo.
I ran one REL No.25 before going to two of them because I could hear and feel the missing bass from the other side.
I also found putting them outside my mains provided greater feeling of depth and breadth in the low end.
This is a function of the cutoff of the sub. For example, if the sub is handling only the bottom octave (40Hz and below) with a steep filter cut-off one will not hear where the sub is placed; the wavelengths are too long in a listening room for our ear/brain interface to locate where these frequencies are coming from.
I have pair of JR Audio D110. Since I have my gear upgraded to made in USA (or to be exact, design in USA and build in USA… ) by PSA, when looking for pair of sub (brainwashed by Paul, that I need Subs to complete my system 
) I look for made in USA stuff too. JRA D110 fit my search. Love it, never know by adding subs can uplift my listen experience. Very happy I was brainwashed.
Yeah, it’s odd. I was crossed over below 40hz and I could tell. I’m not sure how steep the cutoff was, but the sub was integrated with the help of some REW sweeps to flat at the listening position.
There weren’t any telltale objects vibrating, but it was physical sensation that helped me locate the sub.
I don’t have a good explanation other than it’s quite possible the SPL was different between my two ears in the bass region and perhaps one side of the room vibrated more strongly than the other.
Most likely the filter slope was not 48 dB/octave so the sounds you were locating the sub we’re above the turnover freq?
I don’t have subs in my Stereo system because I only use it for music… I don’t think I’ll ever need one.
2x REL S/510
2x REL s/510’s as well.
There really is a surprising amount of information down there in the low frequencies.
These are at the top of my list. Can they be placed close to a corner(s) of the room?
Probably depends on your room but they seem to work for me although I do not have them pushed up tight to the walls.
Great thanks.
I’ll have some flexibility, but knowing that it works outside of a brochure Is cool!
Thanks
I currently just use the NHT built-in “subs” for 2-channel. When I eventually add a HT system, I will more than likely build an IB system with the back wave going to my garage.
Sorry, I meant to say I don’t have them pushed up right against the walls!
Bait and switch…
haha no worries thanks for the clarification. I’m pretty set in my mind on these anyway. I will wait to see if they run any deals in the next 6 months.
I’ll try it out for you soon and let you know!
This article from REL should make you feel more comfortable: link
Great looking room!
Pair of REL S3/SHO. Miss them if I turn them off.
Now the weakest link are the speakers. Saving up to replace them next spring.
A stereo pair of the Martin Logan Dynamo 1100x.
Man, I really struggle with whether to put more $$ into a second sub versus using the $$ to upgrade the L/R speakers. It just seems like the correct answer should be upgrade the speakers, rather than to drop another $3k on a second sub.
In particular in my situation, better to go from $7.5k speakers and one $2.5k sub to:
$11.5k speakers and the same $2.5k single sub.
OR
Same $7.5k speakers and now two subs totalling $5.5k.
I realize the numbers don’t quite balance out but point is the same (the speakers I’d upgrade to are that amount). I gotta think choice A above turns out better???
Anyway it’s probably a few years down the road so I have time to ponder. The “multiple subs versus one for music” movement is really taking off though.
I guess a third option would be upgrade the L/R, sell the current nice sub and get a couple cheaper ones. That one makes me nervous too though across various audio forums.
Ahhhh, first world problems… Stay safe everyone. Stay vigilant, it’s tough but