Subwoofer to mate with Casta model C's.......

I have Casta Acoustic model C's with a 15" woofer, 17" custom horn midrange and 2" custom horn tweeter in each floorstanding speaker. The speakers are a sealed cabinet and are very efficient. My room now is 13 x 19 x 8 but soon will be 20 x 24 x 8 after renovations. I had previously owned an SVS PB13 ultra before purchasing the Castas but sold it knowing I wanted two in the larger room. The svs was a phenomenal performer. Can anyone give any recommendations on one or two subwoofers adequate to mate with the Castas and given room sizes. Budget is not an issue. THX in advance......
check out a site called look at the Seaton Submersive or from JTR the JTR Orbit shifter or the S1 or S2 to name a few.
Since budget isn't an issue there are now a growing selection of manufactures that offer internal calibration and/or equalization which usually makes integrating with the main speakers a matter of infinite personal taste or at the very least a simple automatic no brainer.

Personally, I went from a large 18" to two 12" subs and found the room interaction much more to my liking not to mention they're much easier to locate. On the other hand I find Larry Greenhill's Stereophile reviews and description of large subwoofer systems intriguing and in the case of my old 18" sub very accurate if you're so inclined.

My subs have remote control of most of their functions which makes individual recording adjustments from the listening position a snap. Sometimes a recording could use a little more or a little less low frequency volume and occasionally a different EQ setting which have been preset.

I found it very helpful that the internal calibration offer both auto and manual settings as well as a visual graphic interface with a computer or a video display. In my previous home I found that I had the need for high pass filtering of my main speakers which my subs offer. The conditions of the current room allow running the mains full range.

Good room and mains integration is actually quite subtle and is usually only noticeable when the extra low frequency system is turned off. In hindsight I would have chosen two 10" subs for my 15'X28'X8' room.

@Shiva, where can I find a Seaton dealer in U.S. or Canada?

@M-db, do you think running the subs speaker connectors to the speakers allows for better blending with the mains? In my case with the Casta C's the bass driver is very fast and acurate. I would need a subwoofer(s) that can achieve the lower octaves - 30-5hz with the same acuracy as the Casta's.
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05-06-15 Bacardi "@M-db, do you think running the subs speaker connectors to the speakers allows for better blending with the mains?"

I apologize, my statement is misleading. I used my Velodyne DD Plus' line level High Pass filtered output to accommodate the use of a much lower powered stereo amplifier while one of the mono-blocks was being serviced. This line level high pass method is usually tried when accommodating small satellite speakers to achieve a smoother response.

Are you considering the speaker/high level connectivity method used by REL? I found my short time with a Studio III and this method of connectivity limiting in some important areas. I was able to improve the subs performance somewhat by using an equalized line level signal from my then, DD-18.

Keep in mind my criticizing subwoofer performance with the staggering room variables that confront producing extra low frequency playback can be quite worthless. I do feel strongly regarding the value of ever improving subwoofer equalization and the ability to remotely control deep bass.

If your goal is large air then you might want to expand your search outside the Hi-Fi community to Danley Sound Labs and Meyer Sound. Good luck with your search.
I may look at the Danley subs if they have a scaled down horn that is wife friendly. If you could see the Casta C's in gloss brown grain you would be in awwwww....

I have looked at the latest Seaton submersible sub and it is very nice but the pricing is well over $3000 for dual 15's in one box. I think if the Danley's have something in that range I would be done and not need another. I don't think the JTR's look as nice as they have a commercial look to them(not my cup of tea or my wifes).
@Bob_reynolds, what do you think of the new Goldenear Supersub XXL? To me it looks like a great contender at $1999US. It would match the Castas well in the piano black but not available till late this year.
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I've had a SVS PB13Ultra in piano black recently(sold) and I found with movies it hit the bottom octaves very well but music just couldn't keep up with my other Casta model D8's(2x8"woofers in each). I now have the model C's(15" woofers in each) which definitely hit down to 30ish but I still want the lower end. When I mentioned speed/acuracy of woofer relates to timing of the driver. The Castas are very tight and acurate to 30hz giving the sealed cabinet and custom made horns and drivers. I don't believe any sub can be as acurate as a floorstanding driver in its same driver size. But that's just my opinion from experiences. Since these Casta model C's(28,000) I've got dynamics, speed, acuracy, dimensiality and soundstage I've never reached before. The Svs SB13 ultra looks like a fantastic sub too but I would need to run two of them. I will specify on going sealed as I ran the pb13 ultra in sealed mode.

The Seaton Submersive F2 HP is also sealed with 2x15" drivers. And supposedly reaches 5hz. Two would be crazy and they aren't cheap - $2800 each. I could get two Svs SB13 ultra for $3000 shipped. I may contact someone at Danley to see what they think of my set-up.
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I just know the subwoofer wasn't accurate. The timing wasn't the same from what I heard with the Casta's. I have good equipment running in my system and I know what it wasn't.
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Thx Bob. I am waiting to speak with Danleysound to look into a DTS-10 to mate with my Casta C's. If the price suits my budget I will go with them. If not I think two SVS SB13 ultras may be the next trial-as they have a 45 day trial.
I've been researching, anyone try(have) a Revel B15(A)? I think this is the sub for me. The hookup is the way I need to run with my fast drivers in my Casta's. Hoping I can find one.

The Revel B15 is a wonderful subwoofer. Fast, punchy, "accurate", as well as deep(17ish Hz with boundry gain). I am using mine with an SVS SB13 Plus(95% same as SB13U) and they mate up very well. Though a bit primitive with today's digital EQ software, the B15's 3-band parametric EQ works pretty darn well with integrating your mains with your sub. Very hard to find under $1000.00 on the used market but not impossible.

I also would not hesitate to suggest a pair of SB13U's if the B15 seems too difficult to obtain.

Bill, I used to have a SVS PB13 ultra because of wanting a sealed sub and eventually two. At the time I had Casta model D8's and didn't need the sub after getting the model C's. Now I want to integrate the Casta C's with a faster sub. The Revel B15A seems to have better versatility with blending with the mains which I need. The Casta model C's are very dynamic, fast and accurate to 30HZ. If I find one Revel B15, I will then get another later. My room later will be 22x25x8. That's 4400Sq feet. I'll need two. I do agree with your suggestion about two SB13 Ultras. I just think the 15" driver will play lower for the movie section and dig deeper than my mains as they too have 15" paper drivers in each of them. Very tight, articulate and accurate in a sealed floorstander. They are amazing.