"Musical" subwoofers? Advice please on comparing JL subs

If you are adding a powered subwoofer, you have just added a big messy tone control. Like it or not.  The idea of signal purity has gone right out the window. 

:-)

Merry Christmas

Erik,
I suspect that the OP is planning on buying a powered sub.  I believe all JL subs have built in amps.

Wow--such incredibly thoughtful responses. I simply love that there are so many approaches to finding the right sound (for each room and listener). And, yes, I’m looking at powered subs.

@fastfreight, that’s a mighty, mighty post. You should be the OP here as both you and your system are so deliberate! Your post gave me a lot to think about.

@slimpikins5, your post has also opened my thinking (and I’ve been wanting to hear those Bryston speakers).

I don’t mean to hijack my own thread but after reading these posts I’m now curious about sub integration software. Is there something out there that is known for being effective and relatively simple? I’m not gifted with the science of it but I’m probably more competent than I sound in this thread. A quick glance suggests that many people have used the XTZ Room Analyzer. Any thoughts? I know there’s free software floating around; I just want something that is straightforward to use. 

Part of my thinking is that the Fathom has the DARO system that is well liked, so if I don’t get the Fathom it might be good to have another method for setting up the room dynamics as much as possible. I also think it might be fun for me to learn more about the way that sound works. I wouldn’t have to skip the graphs in the online reviews and jump straight to the conclusions! If the software is effective, I could buy two subs--JL e110, REL, Axiom, etc--for the price of one Fathom AND the mic/software. Can I really put TWO subs in a 10’ x 11’ room?

I’m not trying to complicate things here! It’s fun for me to think about these projects.

Northman,

First off, do yourself the best favor you could ever do in this sport, go listen to the Bryston Model T's.   Most likely you will find the standard 'Passive Crossover' version out there; that is what my pair started out life as.  I run tremendous power here with my large space, 2000 watts per channel at 4 ohms and I decided I wanted to upgrade my T's to the 'Signature' version which uses massive, Mil-Spec built (gorgeous circuit boards with huge air core wound inductors) external PX-1 crossovers with triple dedicated inputs on the back of the speakers for each section.  Ian at Axiom wanted me to ship the speakers back to him for the conversion and James Tanner at Bryston supplied me the pair of PX-1's.   I decided to do the conversion myself as I have a nice cabinet shop in my barn with all of the equipment needed and that way I don't have to pack up two massive speakers on a pallet to ship to Canada and risk damage.   It took me about three days of work to complete everything using OEM parts Axiom shipped me.   The difference in performance with the PX-1 is just breathtaking!   Find the Signatures to listen to.

Secondly, you should really look at the Axiom EP500V4 , this is a fabulous Sub; plus the amp is designed with a DSP circuit which will not allow the sub to be over driven or distort, you cannot kill these speakers.  It's all Axiom/Bryston proprietary designs and ALL of the components are made in Canada, no overseas Chinese stuff.  SVS was completely built in China and uses switching power supplies from what I saw (I burnt up six of their subs, both amps and drivers).  JL I don't know much about but I believe from what someone told me that they use some Chinese components.

Thirdly, I think that if you are using properly designed gear, you should not be using any room correction type software to EQ your room.   I have Anthem for my preamp and it's a wonderful piece with powerful ARC software with a fancy Mic.  But after running it and allowing the computers to 'balance' the room, I turned it off and went full flat with just my Model T's and the amps/preamps and 3 subs.   Hands down, no software EQ  at all, flat just beat the hell out of the software.   When I spoke with James at Bryston, he told me that they never use any software room correction in their spaces and Ian at Axiom said the same thing.   Properly designed equipment should not need anything other than your own playing with speaker placement and location and phasing; which is far more fun too.

If you happen to be in Northern New England, you are welcome to stop in for a listen before you do anything.

Fastfreight wrote: "But we do have two stereo main speakers... and there is stereo information in bass information (not talking about LFE or .1 here). Stereo subs SUPPORT the soundstage and imaging. Not sure if Swarmy subs do this all over the room or not. Seems dubious."

The Swarm is normally sold with a single amplifier to drive all four subs, in summed mono configuration. An optional second amplifier can be added, such that the left channel signal goes to the subs on the left side of the room, and likewise for the right side.

Imo true subwoofer-region stereo is rare at best, but the second amplifier can significantly enhance the sense of envelopment even with normal program material: Set the phase controls on the two amps 90 degrees apart, in what’s called "phase quadrature", thereby synthesizing the phase differentials one might experience in a large room. Credit to David Griesinger for this idea.

Obviously this phase-quadrature technique can be used with two conventional subs provided they have continuously-variable phase controls. I’d suggest locating the two subs along the left and right side walls.  

Duke