Looking for Sub to pair with Dynaudio Confidence 20s

 Im running a Rel S510 stereo pair with my C20s right now in a room 18x15...They just had a price increase so over the 5K bench mark new  but used you could do it..I would not mess with their entry X series..Easy to integrated and no need with all the room correction and  the multi phase chatted about above on other makers.If you want to spend more Id go with Perlisten.

Thanks all for great input. Given my room, leaning toward the JL E110...

Thanks!

Have you considered Dynaudio sub 6 ?

Thank you!

Rogersound Labs was the first company I heard that had a subwoofer back in 1974.

I have a pair of their 10S Speedwoofers and they pair really nice with my towers. I gave the 10S Speedwoofers a try first due to having transmission line design to go lower in a musical fashion.

The 12S Speedwoofer has come out and it is very highly thought of. They are a company that will let you try them out and pay the freight to return [at least they did when I was delivered my pair of 10S]. I didn't send them back.

REL is good but overpriced and lacks variable phase.

As soix said, you need to be looking at 2 subs without question. I would drill down on both REL and Rythmik's websites. Solid choices from top to bottom. I have a pair of Rythmik G22's and absolutely love em. They're a dual-opposed 12" model. They also make a dual 15" (G25). They're known for being smooth and easy to listen to, and I can back that up. The balls-to-the-wall home theater junkies think they don't have enough tactile response, and maybe they don't for that application, but that's exactly what drew me to them. The last thing I wanted was subs that draw attention to themselves. The goal is for it to sound like your speakers are producing all that bass.

Very simple

Get the most expensive REL you can afford. 
Simply tune to blend with your mains 

Good luck Willy -T

@dmeltz 

Hi, As mentioned previously you do not want to do one subwoofer, two is the minimum. 

You have smaller bookshelf speakers hopefully on stands. These speakers have the ability to perform acceptably in a room that large , but it is pushing it. In order to get satisfactory headroom you are going to have to remove 100 Hz on down from them and hand it to two subwoofers at least 12" in diameter (the drivers) via a two way crossover. The best are digital such as the MiniDSP or dBx Driverack. 

If you are handy the least expensive way to get started in subwoofers is to build them yourself from kits such as those sold by Parts Express. They even have a selection of excellent plate amplifiers although I prefer outboard amps for subwoofers. QSC makes excellent amps for subwoofers at very reasonable prices. You can get two subs, amps and crossover for less than you could buy a single high quality 12" subwoofer from JL Audio. 

If you go with one subwoofer using a low pass filter you will be very disappointed in a 400 square foot room. 

how about 2-REL t/7x or 2-REL t/9x subs? For 2 channel systems these are some of the best sounding subs in their price range.

REL is famous for easy implementation with a wide range of speakers using the high level inputs. REL has a 60 day home trial with free shipping. I owned REL from the early 2000’s with Totem speakers

First, you want to get two subs not just one as the performance improvement is substantial.  For about $2100 you could get two SVS SB3000 subs that come with software that helps greatly with integration, and they offer a long trial including shipping both ways so no risk.

https://www.svsound.com/products/sb-3000
 

Or, for a little more $ and even better performance but with no integration software you could get a couple Rhythmik F12G subs…

https://www.rythmikaudio.com/F12G.html

Either way you’ll be in great shape.  Best of luck.

Thanks all! Open to new or used. <$5K

to get a sub that can be subtle is probably a good approach. At least when you are not into shaking the room and your wig flying off

My Room is 13 x 19 I have had the confidence 20 speakers, and there was no need for a sub base. My room has a big picture window, hardwood floors with area rug. I also have some good room treatments. Very nice fast bold bass. Not sure what you have for an amp? I now have a set of confidence 30 Speakers, the base shakes my house. The difference between the 20 & the 30 speaker is huge. With the size of your room, you should buy a large floor stander.

As always try to get an audition.  I think SVS has some kind of trial offer? I have one larger sub but always wonder if I should have gone with 2 smaller ones. 

Not JL audio, mine are always breaking…

I don’t really understand why subs need to be "paired" with speakers.

Doesn’t the question come down to sub type, room size, style, and price?

After all, most subs will be able to assume the burder of reproducing frequencies below almost any speaker. That means that the fundamental question at stake in a choice of subwoofer has nearly nothing to do with speaker type and nearly everything to do room acoustics. This is how I’ve understood the basic situation.

Budget?  And are you looking for new or used?

ATC C1 MK2 sub