Sealed Subwoofer Recommendation

I am looking for a good sealed subwoofer that'll integrate well with my Dynaudio Evidence Temptation speakers. I have a tremendously large room that suck out bottom 1/2 octave of bass from my speakers and I don't feel like upgrading to Master model and pay five figure more to obtain the bottom 1/2 octave. I've tried Velodyne DD15 and it worked somewhat but found it to be too slow and loose sounding. Up for consideration is JL Audio Fathom F113 that Absolute Sound and Home Theater praised but one of my friends say that this is one of those King Kong subs that is not very articulate and he recommends Focal SW 1000 Be. Anybody heard this? Has anyone heard Zu's Method which is dual 15 inch paper cone sealed subwoofers? How about Martin Logan Descent or VMPS very large array? Or Dynaudio Sub 500?
JL Audio is about your only choice that comes to mind. Also, if you can find one.. a REL Storm V. Seems like Sumiko doesn't want to sell a good sealed box sub.
You did not have the DD-15 setup correctly.
If you have a large room...go with a pair of subs. Place them near the mains and the blend will be seamless. While I have never played around with the Velodyne DD15...most agree that it's a pretty darn good sub.

The fact that you could not get it to blend properly for only the bottom octave (20hz-40hz) hints at one of two did not set it up properly, or...your room is so large that you need two subs.

I use a pair of VMPS subs with my Apogee Duetta Signatures...With a lot of trial, the blend is seamless in my fairly large room.

There is nothing loose or slow sounding about a DD-15. It's possible that the sub was exciting room modes to a greater extent than the Temptations and thus seemed to loose and slow.

Do you have any bass traps? What are the dimensions of your room?
DD 15 doesn't work then try this one:
Take a look at Bag End.
How tremendous is your room? If it is really too big, maybe none of the sub will work well enough.
I would suggest a pair of JL Audio f113's. I am certain they would resell for what you can find them for new with all the buzz.

I have a pair in my listening room and have never heard a tighter, more musical subwoofer yet.

Now - I haven't heard them all. However, I was skeptical of their "praise" until I heard them. Still makes me shake my head trying to discuss their performance.
If a sub sounds thick then it's crossover is too high. There is no such thing as fast bass. If the bass is fast, it is not bass. The ability to blend with smaller speakers is the job of a good crossover and room setup. Have you ever seen a small bass drum? A small sub, in order to move as much air as a large sub, has to move further than a large sub. Therefore a small sub cannot be any faster than a large sub when making the same amount of bass.
Room acoustics may well play a larger role in determining the quality of bass reproduction in the home than does the relatively small difference between various high-quality subwoofers. An acoustic solution would be to use two or more smaller, high quality subwoofers asymmetrically scattered around the room. Multiple low frequency souces smooths out the in-room bass response. This has been documented by several researchers in the field, and I could provide references if you would like.

Rwwear, I once saw a video of Neil Peart playing what looked like a toy kickdrum as part of his drumkit. The kickdrum was ported!

Stereo phile says

one of those King Kong subs

I have just what the doctor ordered;

King Kong Sub
Cool Audiokinesis.
I going to just put the Seaton Sound Submersive out there. I have one going in my room this week end. It is a relatively compact dual 15in sub. It has a 1000 watt amp. All indications is that it is a fantastic performer. Plus it is less then the F113. The SQ has been reported to be fantastic. You can find some info on AVS. There is also a review of the SW1000Be on avtalk. Just goto the sub test section and you should find it. If you are interested in the SubMersive email me, and I will give you Marks info.
Wow, I havn't visited my own thread for a while since I've gone skiing vacation. Thanks everyone for the great posts. My friend also pointed out to me that two or stereo subs works much better than a single sub. The current issue of HiFi+ has a great article of this that my friend showed me.

My large room is about 1,500 square feet of space that has to be filled. Beyond the listening poisition there are three adjoing rooms that makes up the total space in a cross like shape.

To smooth out the room modes, I will go with two subs positioned behind the main speakers against the front wall. I've got into a pilot program with a subwoofer manufacturer who will actually provide me with two subwoofers that are sealed 15 inch paper cone drivers with some kind of loading, factory provided Rane dsp processor and 3 day rental of professional test equipment that the factory will dial into the test equipment remotely and set up my system. This ought to be interesting.

I did listen to the JL Audio Fathom F113 at local dealer Atlantic Audio who carries Dynaudio Evidence Temptation, Masters, and JL Audio Fathom F113 along with SIM Audio electronics in their main showroom. It was only one F113 subwoofer in the showroom. It was being crossed at 40hz to augment the main speakers. I played around listening to Temptations and Masters comparing the sound both with and without F113. First of all, since the room was smaller than my listening space both of these speakers did darn well in the low frequency range and there really wasn't any need for subwoofer augmentation with F113 subs especially with Master model that has 4 each 10 inch drivers per speaker. What little difference it made with Evidence Temptation seemed insignificant. I did try just listening to the subwoofer output as I have done with other subwoofers and played around with different crossover points and gain of the front panel. F113 seemed to sound pretty quick in its prodigious bass output and from my memory it might be a little better than Velodyne DD15 bass. Still F113 didn't bowl me over with its integration with Temptations and it didn't sound like the coherent bass sound of the Master model. I think digital subwoofer and room correction with Rane, Tact, or DEQX could have made this integration much better.

So, I'm waiting for delivery and trial of these new subwoofer designs which should come in 3 more weeks.
We have installed hundreds of the 2WQ vandersteen subs which are sealed with great results. the high pass will also
allow you to experience a new level of transparency
Well, I ended up with a pair of JL Audio F113 subwoofers after trying all kinds of subwoofers. I am using TACT Audio 2.2XP to cross these subs to the main speakers with time alignment and room correction. I finally got what I'm looking for. A seamless integration of mains with subs and deep tight bass with weight that you hear in Disney Concert hall. I am very happy with this set up.
deep tight bass with weight that you hear in Disney Concert hall.

I know exactly what you mean. I spent a few minutes with Ben Lilly last year and he gave me a few tips on my modest setup - no design just some back of the envelope advice. Excellent audio engineer - best advice I ever got.
Try the Manger subwoofer.Tight and fast.
The Jl makes the Vandy's finally work. I hate to say this because I own a pair of Model 5a's and 2 ce sig's and I never in a million years thuoght I would need another sub for the Vandys but a got a JL 13 and it KILLS the subs in the Model5a's. Just one Jl sub makes the 5 sound wonderful- It get that little bit of detail that everyone out there(and yes you know) that lots of audiophiles say they love Vandy's but,they need a little more detail- they are too soft-you go on the discussions on Vandersteen and there is several people that have sold there Vandays (because the lack of upper detail) and the built in subs are not tight. I called Audio Connection and one of there employees(no names) even told me the B&W 800d kills the 5a's on pure detail. The JL Audio makes the Vandy sing.