SVS or REVEL Subwoofer

The Dynaudio 18s  is under $1799. Dual opposed 9.5 in drivers, no port. 500W amp.

https://dynaudio.com/professional-audio/subwoofers/18s#product_downloads

Very controlled and musical and gets down to <~20hz

The Dual opposed drivers mean there is zero vibration: all the sound comes through the air rather than the floor.

It has some built in EQ settings to match them to various Dynaudio monitors: both these can be bypassed and you can set the crossover point directly or my pass the setting complete and mage the bass with room correction software

I use it with my ATC SCM 19s and Dirac Room correction. Very happy with teh result.

There is also a shinier version the "Sub 6".  More expensive but functionally identical except that built-in EQ settings (which you would not use anyway)  match Dynaudio home speaker models rather than their studio monitors,

@rick_n 

I like your logo.

Sounds like you're supporting the REL T/9x, correct?

If I'm feeling like it's my lucky day, should I bother with the upmarket REL or B&W models?

drlou77

The point made about 2 subwoofers  being too much for your room is a very valid point by rick-n

There is a guy on youtube who reviews many, many subwoofers. He reviewed both the SVS and REL. His review of the HT/1510 is one that should be informative. Name is Nemo Propaganda. Check him out...

Not sure why people are making comments about two subs being "too much for your small room".

I suppose if you turn the volume up on both, then the two would overpower the room, but two subs are only as loud as you want them to be.

It's like saying a Porsche Spider has too much horsepower to drive the speed limit.

Makes no sense.

The reason to have two subs is because two subs sound better than one and will give you smoother low frequency response regardless of the size of your room.

I do support the REL T/9x given your original posted budget.  When you go up the line, subs will generally dig deeper with clarity.  Good brands, up the line, will have better constructed drivers, more inert cabinets and more power.  You have excellent speakers and really just need to augment the bottom octave.  In real world use this I see it as the 25-50hz range.  The T/9x will do this and the S/510 will do it better.  The S/510 will roll off lower and give your system more weight.  It would be unfair of me to speak about the B&W sub since I've not heard it.

When you meet with your dealer, make sure they are familiar with your room.  If they haven't see your room, bring some pictures to share.  Also, be sure to talk about the structure of the floor and what's below it.  This is important to how the sub will play in the space.  Good luck and cheers