[SteveFord]

Does anyone have any experience with this unit or company?

https://rolls.com/product/SX95

What I'm thinking of doing is Crown amplifier which I already have, maybe this Rolls unit, two cylindrical SVS subs with my Magnepan 3.7 system, run the Maggies full range.

I don't know if this would be the way to go or not so any thoughts?

[Letitroll98]

Maybe the coffee hasn't kicked in yet, does SVS offer a passive sub that I'm not aware of?

[Phil A]

For music (my main system is an integrated AV System), I use two old Rel Storm IIIs (for many years) connected via the high level crossover (and they are crossed over at 22Hz) with each one connected to a channel of my stereo amp.  As far as crossovers, there are other companies that make them as well (e.g. Bryston) such as https://www.marchandelec.com/electronic-crossovers.html   If you already have the subs then a crossover probably would be the most economical approach.  They sell the crossovers you linked at Parts Express - https://www.parts-express.com/pro-audio/signal-processing/active-crossovers

[SteveFord]

I went ahead and ordered one, we'll see how it works.
The Crown has volume controls so more stuff to fiddle around with.
These are OLD SVS passive subs which is really what I prefer, keep the electronics away from the vibration.

[mcgsxr]

I am recalling the Crown XLS amps also have a built in Xover in the digital domain.  Could you use that to trim the frequencies and the trim pots for volume?

The Rolls piece should for sure mind you. 

[m.oreilly]

I would recommend not running the Maggies full range in this situation. It works, but when both the mains and subs are crossed with a suitable xover (I am using a cheap but wonderful old NHT X1 along with a QSC power amp), the results are pretty much seamless, as long as the subs are not too far or too far behind the mains. I was running Peter Gunn modded MMG along with dual 18s and the result was just awesome. I know you may feel that you want the most out of the Maggies, but xovering them will really make them seamlessly blend with the subs.

Michael

[SteveFord]

I got it, it just took the smallest amount of volume to get those subs to blend in right with the 3.7s.
Crank up the gain too much on that Rolls unit and it sounds terrible but back it down a bit and it's just right.

It took a few trips back and forth to the couch to get the level where it belongs.
When I was adjusting the sub gain my ear was right alongside the speaker so I couldn't tell how loud the speakers really were, I was mostly hearing the subs.  Get back to the listening position and the subs were way too loud so back again...

[lokie]

Are you all using high pass filters or just coming in under the mains?
I'm using a ROLLS product as well but it is just a booster to allow the home audio preamp play nice the the Pro Audio Berhinger 2496 which likes a little hotter signal. it also does XLR/RCA conversions. Nice little product.

All works fine but thinking about the next best thing... Including a high pass filter. Right now, the mains run full down to 40Hz and then the Berhinger kicks in. I have the common big dipper at 60Hz and  would like to equalize with the subs/Berhinger and roll the mains off between 80 and 100Hz.
I know there's lot of easy ways to do this but I cant get comfortable with sending the main signal through a high pass network. the few products I've tried just crushes intimacy nuance and sound field.

[notany]

I have been running passive dual subs for some time now and I can't recommend a high pass enough. If you are running separates or have a processor loop available try the PF Mods inline filters.  They are cheap enough to try for fun and don't mess everything up. I'm using a NAD C658 as my pre and it does all the work, even before Dirac. The PF mods is passive, no digital nothing.

[NoDisco]

I have two small rels (T2, I think). I have them at a whisper and they do wonders for my omegas. I don’t think they contribute to stereophonic imaging at any volume…but it’s nice to have 2. I think they’re crossed around 100hz and below.

[SteveFord]

I have a Crown amp here which was actually on a road show many years ago when they first came out.
It's still going strong!
Magnepans hooked up like normal to a conrad-johnson preamp w/ two monoblocks, passive subs to the Crown, Crown to the Rolls sub output, Rolls inputs to the preamp's unused set of amp outputs.
Crown set to stereo default, gain on the Crown at full, crossover on Rolls at 75, gain on Rolls at a little under 3, set to stereo, phase 180.

I believe I've described that correctly, everything is buried in a cabinet.

From futzing around with it a little bit that seems to work the best here.

[lokie]

I have been running passive dual subs for some time now and I can't recommend a high pass enough. If you are running separates or have a processor loop available try the PF Mods inline filters.  They are cheap enough to try for fun and don't mess everything up. I'm using a NAD C658 as my pre and it does all the work, even before Dirac. The PF mods is passive, no digital nothing.

I didn't get the same results. Lots of gain loss and turned 3D imagery into noD.