sub s 2 Sunfire Juniors, or 1 Sunfire True sub.

The big question is ..are you going to run stereo subs or mono? No doubt one large mono sub will go deep. But can it be as articulate as two subs run in stereo ? I really doubt this ..since the duty of left and right LFs are handled separately when using two subs in stereo. When there are drum kicks in the center stage both subs step in to do the duty.There's no way one mono sub with a single woofer can be as clean or accurate as two stereo subs IMHO. I would try the junior first run in stereo with the one you already own.
I found the Sunfire True in mono rather lethargic.

Hi there,

I just want to add that I have the true sub MK IV mated to B&W Nautilus 805 currrently. The sub can be muddy and slow w/ excessive overhang.

Luckily, I found the cure by putting it on a lovan jazz 6" stand. The transformation is almost night and day as the issues w/ speed, cleanliness, overhang cease to exist. Now, the blending is about seamless and unobtrusive. I cannot recommend the stand more highly. Have not tried other brands/stands but I am sure the effect is comparable. I believe the reduction in the nasty characters above or improvement brought to the whole musical presentation is even more pronounced than careful stand matching for your main speakers. Those low-frequency rumbling of a subwoofer requires more taming than a regular set of speakers. Plus, when its associated problems isolated and corrected, your speakers will sound even more musical, dynamic and clean.

Hifimannen,

I used to have a Sunfire Signature a real beast and a I liked it a lot. However I tried two Juniors together and found that it was more musical. The Juniors seemed to be faster and and less obstrusive.
But if you really like a lot of deep bass go with the True Sub, it goes deeper.
For myself the Junior are just fine and I don't miss the Signature.

I would get the Sunfire True Sub. I believe it will go lower than the Junior. Two Juniors would give you plenty of midbass volume but might still be a little short in the bottom octave. The True Sub would handle most of the bottom octave and would be better unless you really need a lot of volume (not likely with the Cubs?).