[subsonic1050]

I'm looking at building the NX-Treme and likely a set of servo subs as well. My room is 14x19 and is pretty extensively treated. Right now I'm running a pair of Paradigm X15 defiance subs which aren't bad, but looking to decrease a bit of the room boom and increase the speed quite a bit.

My question is regarding going with double vs triple servo subs. Is there an additional benefit to the way the triples are crossed that allows each sub to get a more even response or is it just additional volume we're moving so that each one doesn't have to work as hard? Trying to decide whether 2 dual H frames would be more than adequate for a room my size or if I should really be doing the triples. Thanks!

[mlundy57]

My 2 cents is to go with the triples. Not because of more volume but because of more body, clarity, and effortlessness.

[subsonic1050]

It does seem that most people end up going with the triples so it must be with good reason. I guess I'm just trying to understand *why* there is that much more body, clarity, and effortlessness. I'm definitely used to a traditional box subwoofer and not these servo subs (never even heard any in fact). My brain, which is used to the box subs is telling me that 4 12" subwoofers in a room of my size is way more than enough. When people are building the triples is there a difference in the way they are set up (wiring, crossover, front/backwards facing), or is the load on each driver just reduced to such an extent that it makes it easier for all 6 drivers to produce a faster, more accurate sound than 4 drivers can manage?

[mlundy57]

Your last question is the answer.

You can’t equate bass output per driver from a boxed sub and open baffle subs. OB subs do not pressurize the room like boxed subs do so don’t expect the kind of boomy slam you’re used to. Six OB sub drivers will not be overkill in your room

[Jaytor]

I built my triples with all the drivers facing forward, but this was primarily for aesthetics. I don't think it really matters much. Having one face backward will move the center of gravity forward a bit which might make them a bit less tippy, but I haven't found this to be a problem.

When you have three drivers per sub, each one is working less-hard with less excursion. This will reduce distortion slightly, particularly frequency modulation distortion. This will also create more source locations for the acoustic energy which could potentially smooth out the room interactions.

Another alternative you might consider is to use duals next to your NX-Tremes, and also use your existing subs at the other end of the room or on the side walls. Having more low-frequency sources will excite the room modes less.

More sub drivers does not mean more bass if they are set up correctly. But it will allow you to achieve a smoother bass response at more locations in the room.

[Early B.]

Just get the triples and all your questions will be answered the moment you press, "play." 

[subsonic1050]

Haha, OK! Well I don't intend to argue with any of that! I plan to put grills on them - if that is the case and the aesthetic downside of having the backwards driver exposed isn't an issue - is it best to put one of the drivers in a backwards facing arrangement?

Thanks for the help guys.

[Dagoods]

Agree go with the triples you won't regret it! I almost went with the duals but so glad I did the triples!

[cjsailer]

Can you start the modular flat pack that jay does with two drivers per sub and then grow into three drivers if the dual drivers seen a little thin?  Refinishing the cabinets might be a pain with this approach.

[subsonic1050]

One more question... where are the plans for the triple cabinet? On Danny's site I see the plans for the double, but when I go to the triple there isn't anything there. Does anyone have a copy of the plans?

[zenfishbike]

This may be the least credentialed reply as I haven't heard the OB subs yet though I do have the components for a dual set sitting in the hall. Prior to making that purchase I scoured this site and can save you some time by saying that if you have space for NX-Tremes you likely have space for a set of triple subs and they are hands down the preferred arrangement to compliment them. I'm going NX-Otica in a slightly smaller room (13x16x8), hence the duals, however I did future proof them by getting the 16ohm versions which are required if you go triple. I'm going to build the cabinets with expansion in mind.

[krazy4]

I love my doubles, but if you can, might as well go with triples.

[Vince in TX]

My room size is similar (15x20 - odd shaped at the back), and I went with a pair of duals (Servo Sub Kit 4).   Part of my thinking was the theater screen height.   The X-Statics would cover the screen if I didn't have enough width on that wall (which I do), but the triple subs might have been too close to the bottom edge of the screen.

[jn316]

My room size is similar (15x20 - odd shaped at the back), and I went with a pair of duals (Servo Sub Kit 4).   Part of my thinking was the theater screen height.   The X-Statics would cover the screen if I didn't have enough width on that wall (which I do), but the triple subs might have been too close to the bottom edge of the screen.

I went with doubles for that same reason. Never heard triples so I don't miss them...and am loving my doubles! Also, if my room ever changes, I can add another driver down the road with a single module from Jay, or just build a new cabinet (built my current one...not hard to do and not too much cost)

[Early B.]

My room size is similar (15x20 - odd shaped at the back), and I went with a pair of duals (Servo Sub Kit 4).   Part of my thinking was the theater screen height.   The X-Statics would cover the screen if I didn't have enough width on that wall (which I do), but the triple subs might have been too close to the bottom edge of the screen.

Consider three doubles. Same output as triples, but with more placement flexibility.

[HAL]

Another option is to ask Jay about the fully modular OB H-Frame sub cabs as flat packs or built.  This way you could start with 2x12's and easily upgrade to 3x12's just adding a modules.

I have a pair of modular 2x12's and adding the extra pair of 1x12's for 3x12's once the flat packs I glued are back from painting.  Just remove the bolts, add the models and then reinstall the bolts.

Good luck with your choice!

[Vince in TX]

Consider three doubles. Same output as triples, but with more placement flexibility.

Interesting since I was considering three subs anyway at some point - two in the front of the room and one in the back.

[pwag]

I settled on 4 ea 12" doubles that provide a lot of flexibility -- stack them to dual quads or split them into 2 systems or spread them around. I made the top and bottom plates same size so I can stack them laying on their sides as well.  This approach also allows for a more budget-friendly growth... start with 2 doubles, add a 3rd and then a 4th.  The triples are nice but you are locked into the height which for smaller rooms could be overwhelming (people move and downsize).