I am considering upgrading my Paradigm Ref Servo-15. I am seeking more musicality and tighter definitive bass as well as retaining good strong impact for theater. The servo-15 satisfies the theater needs but seems slow on music. I have just returned from auditioning the Monitor Audio FS212 and the Rel Storm and Stadium. The Stadium would be my choice of the three but 1) it is actually larger than my present sub and I was hoping to recover some floor space. 2)it was 1000.00 higher in prie than the other two. So my question is what do my fellow a'goners
You might try an inexpensive pair of Audience Conductor series ic's with your sub. It's amazing how the entire line of Audience cables will minimize time smear and provide at least some subs a much more accurate lower bass reproduction. Some Audience dealers will provide up to a 60 audition time period.

Secondly, it's highly probable that the type of bass you may be dreaming of simply cannot take place with your current strategy. Why?

Primarily because the amplifier sections of some to many active subs simply will not provide the absolute control over the subwoofer driver that is an absolute must. The sub amps may be satisfactory or even good, but certainly not great. (I'm a believer that if the subwoofer mfg'er's amplifiers where really that good, they'd spin off a whole new line of amplifiers.) It has been stated on more than one occassion that many very expensive 2-channel amps also fail miserably at the bottom end. Therefore, the sub mfg'ers are not alone here.

You stand a far better chance at obtaining the deepest, tightest, most well defined bass if you should instead opt for:

1. A pair of full range speakers like the Von Schweikert VR-4 Gen III SE's (retail at $6k) that supposedly accurately go down to 16Hz. (Keep in mind most subwoofers cannot not go down to 16Hz). And a full-range speaker like this also eliminates any potential crossover problems that seem to concern many.

2. Finding the best amp possible to help get the speakers accurately reproducing way down there without sacrificing any other part of the frequency spectrum. Good luck finding one.

3. Finding the best speaker cable that eliminates/minimizes the time smear that is so commonly found in most cabling. Not to mention purchasing such a cable without having to sell the farm.

As someone very knowledgeable once told me... "Bass is slow ... It is the high frequencies that provide the illusion of speed."

There are many factors that can affect bass performance and before ditching the Paradigm you might try optimizing its performance by fiddling with its location in the room, crossover frequency, and phase control. I got my Servo-15 to mate seamlessly with InnerSound Eros electrostatics (which are very fast speakers), so something may be wrong with your set up. Bass is extremely room-dependent and simply buying a more expensive sub may not solve your problem...
Plato thanks for the advise I have tried numberous adjustments to the X30 furnished with the servo. I am really limited on sub location, I could rotate it if you feel that may be beneficial. Have you ever tried another crossover? I have listened to the Innersounds and you are very fortunate indeed.
I agree with Plato. I don't know your sub, however, I have mated ML with a genesis sub. It may be that to get an optimum mix there are four things you should try. 1. Lower the crossover point. 2. Check to see if the crossover slope can be changed to something like 24 db or even faster 48 db. 3. Change the location to right between the speakers and slightly forward or in a corner behind one of the speakers. 4. Finally have you tried bass traps?
Get the Stadium and stop worrying. It's just so much more musical, and still has astonishing output capability. Avoid the temptation to buy the Storm, it's not nearly as good.

And contrary to the above:

(1) Bass "speed" is indeed an issue, and is indeed difficult to achieve with very large drivers without getting very expensive (as in, many times the cost of the driver used in the Paradigm). I'm not disagreeing with the theoretical statement that bass is slow compared to higher frequencies, merely stating that in the real world, good-sounding 15" drivers are VERY expensive.

Technical diversion: You always have to think about these issues from the perspective of TIME. Just as an example, if a midrange driver has a 1 degree phase lag on a 1 kHz pulse (due to inertia), that is a delay of about 0.04 seconds. If a subwoofer has the same degree of phase lag, the delay at 30 Hz is 1.25 seconds! It suddenly becomes clear why the bass driver must be so good if it is not to sound "slow" compared to the rest of the system.

(2) A properly set up sub/sat system will almost always be superior to an equivalent full-range system, simply because it is almost impossible to set up a single box in a location which optimizes both imaging and bass response. It's more difficult to get the sub/sat right, but when you do, it's amazing.

(3) It is quite easy to design a good sub amp as long as it's not required to sound perfect in the mids and highs. The main requirement is a really big power supply, and this is obtainable quite easily. This is the other big advantage of the RELs: the signal to the sats never passes through the sub's circuitry, so it can't possibly get screwed up.
I recently posted a question here (and on AudioAsylum) looking for recommendations on a tight, fast, musical 15" subwoofer for 2-channel music only in a fairly large room. The majority of responses from both threads were for the Paradigm Servo-15.
Theo, rotating the sub can have a profound effect since the enclosure is around 22" long. In fact, in my system, I had the sub facing the wall (at mid-wall) and I had a standing wave that just wouldn't be tamed. But I rotated the sub so that the woofer faced out into the room, which effectively brought the driver another 22" away from the wall and now that big peak has been largely tamed. And facing it to the side instead of straight ahead has a large effect too, so you may have a couple of options left before you think about moving to a more expensive sub. I think it also helped mine when I put it up on 3 BDR cones, and by all means use that level control too.

The RELs have been getting great press, but even the RELs are subject to the same laws of physics that ultimately determine the performance of any and all subwoofers in a given room. So my advice stands.

That said, if you are very limited as to where the sub can be placed it may not be possible to achieve good results in your room with any subwoofer. Try the positioning and let me know if that works for you.
The room has a larger impact on bass transient response than the drivers.
If there's a large peak in the bass response of your room, the bass transient response is going to be slow and boomy, regardless of the quality of your subwoofer.

Bass traps are the only real solution to "slow bass" in most rooms; it is not possible to have too much bass trapping.
Parametric equalization can also be used, but this only compensates for amplitude, and does nothing to fix the room resonances that cause the amplitude problems in the first place, and attempting to equalize a large null can increase distortion and reduce amplifier headroom.

After fixing the room, distortion and doubling from the subwoofer itself become the next important issues to address, and on this point, high-end subs will begin to dramatically outperform low-end subs.

ie: the sonic differences between subwoofers are almost always swamped by the much larger effects of room acoustics and standing waves.
It's a small rainstorm within a hurricane.
Well said, Snickelfritz! That was almost poetic. :)
jdombrow, did you purchase a sub yet???????
I'd definitely experiment with different sub positions and angles, and the crossover/volume settings on the X30 before getting another sub.

I have an old NHT SW3P being powered by a Bryston 4b, controlled by a Paradigm X30 and have achieved satisfying bass for my small room. Opting for a lower crossover setting helped reduce boom and give the illusion of better speed and pitch. And, finding an unorthodox location mid way along the side wall facing in helped too. It can take a lot of work and listening, but the results may surprise you.

Two smaller, faster subs might be a better solution. That is if you can swing the extra cash and have the room for them.
Theo. You have yet to even hear your system if you are running your mains through the x-30 crossover. To be blunt and honest...the x-30 crossover is simply a piece of junk.Borrow or demo a decent crossover and you would be amazed at how great the servo 15 really is!
I would suggest that you audition a Super Cube Subwoofer from Definitive Technology. Very impressive bass output, small size, integrates well with full range and monitor speakers, and relatively inexpensive at $1200 retail. In my system it is quicker and more musical than the REL Storm III and the Sunfire Signature Sub that I have previously owned.
Yes, I'd definitley NOT run any main speaker through the X30. I run my ProAc monitors full range and use the X30 only on the sub. The X30 muddied up the midrange and killed the air when I hooked my ProAcs to it.
Gunbei, I am running the sub only through the X30, the speakers are direct from pre/pro to amp. I have looked at the new Digital Velodyne system but am waiting to get a proper demo. They claim it is the "everything" sub if you get a chance look at it on their website.
Hey Theo, that's interesting. Over the years with every succeeding model change it seems that Velodyne has been targeting the home theater market with less and less emphasis on the music crowd. It'll be interesting to see how this new subwoofer line performs.
I have a problem with running the main speakers full range with only the subwoofer(s) bandlimited. IMHO, one of the advantages of using a subwoofer is to keep those large excursion low frequencies out of the main speakers, because they have an adverse effect on the midbass which the main speakers produce.

Also, I question the use of low (50) frequency crossover rather than high (90). Most people look at how low the main speakers go, and set that as the crossover. I contend that it is just as valid to look at how high the SW goes, and set that as the crossover. Of course this depends on your SW capabilities. In my case, I have selected 90 Hz over 50, and 70 which I have tried out. My main speakers, MG 1.6, can go to about 40 Hz. Of note is the fact that my six driver SW system includes three 15 inch JBL drivers that can go up to 800 Hz.
I would strongly recommend you cut the low end out of all your speakers except the sw. That's the purpose of the sw.
Gunbei, I have listened to it breifly yesterday, the dealer was too busy for a complete demo. But I am enticed.
take a look at it on the Velodyne website. It is the Digital Drive system. Very flexable in setup and precise with a microphone and video display parametric and para- graphic equalizer using the feedback from the microphone. It promises to optimize bothe theater and music. and has 6 pre-sets available for types of music/movie that can be programmed and accessed by remote. This may be the one