REL G2 or JL Audio F112 ..thoughts for 2 channel

Sonus Faber makes a Cremona Subwoofer M. I wouldn't spend my money until I'd heard the Cremona M/Subwoofer M combination.

However, the Cremona sub is pricey at $7500 list. So otherwise I'd be looking
at the JL. I think they're way ahead of the competition in bandwidth, speed,
dynamic range, and therefore the ability to blend. I've heard a pair of
Magnepan 20.1s blended seamlessly with a pair of Fathom F212s. Great-
sounding combo.

I LOVE Cremona Ms; adding a pair of JL F112s would turn them into a
seriously resolving, highly dynamic full range system.

I think the sub integration issue is a bit overstated. I've integrated subs into at
least 7 different systems, most of them music-based 2-channel. Yes, it can be
bit of a PITA, but it's not like you go weeks on end moving, listening, tweaking,
measuring. Generally I've found that I can dial in something listenable within a
half hour, and after letting it run in for awhile, I may have to do a second run at
it that may take 2-3 hours. I've integrated subs into at least 7 systems, some
surround and mostly 2-channel. The more you integrate subs into systems, the
faster and easier it gets.

And get the JLs. I recently read a review of Focal Diablo Utopias mated with a pair
of JLs and the resulting $18K rig provided around 90% of what you get with the
$185K/pair Grande Utopias. Compared to ponying up the price of a really good
pair of true full range speakers, spending a few hours integrating the subs is
well worth it.

REL has the advantage of being able to blend high and low level signals. OTOH, at least of the REL test report I read, the REL simply added a sharp bass spike centered around 45 Hz and it was entirely up to the user to move the sub around the room and fiddle with levels and placement to get this spike to broaden via room boundary reinforcement and blend with the rest of the system. Measurements here.

By comparison, the JL had a broad, flat frequency response that didn't start rolling off until around 20 Hz. The JL drivers are a thing to behold, with massive, deep castings and a magnet that could probably pull a car from across the street. If you're really down to JL and REL and you are willing to spend REL money, you *really* need to audition JL. Fathom F113 measurements here. JL subs are essentially flat from 20Hz to 80-100 Hz depending on model.

I also read a review of JL's entry-level F110, where the reviewer felt the 10" sub flap his pantsleg from 10 feet away. The F110 is about the same price as the REL R-328.

I heard JL F212s blended seamlessly with Magnepan 20.1's. If they're fast enough for panels, they're fast enough for anything. Also, they are capable of such high output they can be brought out into the room next to the stereo speakers.