Small footprint subwoofer

I would heartily recommend the Martin-Logan Dynamo 800X subwoofer. $900 retail currently.  Sub is 13.7”x12.4”x13.1”. Full app control plus a useful ARC DSP app that can use your phone as a microphone. I use a pair of these to extend the response of my Bowers and Wilkins 805D4. The ML app makes it easy to tweak the settings from your listening seat. Both speaker and line level inputs.  Don’t believe me however, read Larry Greenhill’s review in Stereophile on his successful experience integrating these with a pair of Quad electrostats. 

highend64    'As far as the position of the Hsu sub, yes it is in a near null position by not quite. That is why it is off centered to compensate the difference. I have the tools to do measurements so finding the best place for the sub is not a problem.'

Just curious. Is this the room location the Rational software calculated or just an interim compensation?

All the best with your situation. Take care.

The KC62, SVS 3000 Micro, and REL T5x are all excellent mini-subs. I would add the Sunfire - which I have - but they're gone. In your small room I expect the KEF would work best, but if budget is a determining factor, then the T5/X. The SVS offers better control via their app, and while not as sophisticated as the KEF, certainly offers incremental value over the REL.

Thanks for the responses. I have purchase the REL R218 and I am currently auditioning it. It might be too early to comment on its performance but so far I am really enjoying how it is sounding. The bass is extremely clean and articulate for it size. I was very easy to seamlessly integrate with my speakers. However, with the sub I notice a few flaws I am somewhat disappointed. First, the R218 has a class D amp rated or 250 watts where as the STF-2 is rated at 200 watts. As far as gain level, I had to max out the gain on the REL to get at least acceptable level and this was used for both low and high level(speakon high level cable). With the STF-2, all I have need to set just less then half ways. This might not be a fair comparison since one is a sealed and the other ported. Second issue is that the REL for me does not go as deep and as the Hsu does. Both subs integrate well in my system and perform well but I felt the REL lacking impact with certain music. It does however sound tight, natural and articulate and this is great but the Hsu does have better impact.

@m-db To answer your question, mostly yes. It was measured at the listening position mostly and other parts of the room. All measurements are done in real time and delayed to compensate latency.

High level REL connection is a great way to go, because every amp’s final output stage has a sonic “color” that will help your sub disappear as an extension of your main speakers’ bottom end. In my situation, the fast down-firing 8” In the REL T5 melts into the 8” Kevlar woofer of Wharfedale Heritage Lintons. Adds only richness and teeny bit of attack as I’ve got it adjusted.