It is time to review the Bose difficulty.
Anyone who has designed loudspeakers has doodled with the idea of a system built round small speakers. However the laws of physics beat you every time.
The problems. Small speakers exist that have a good midband and high end response. However, even a small speaker in a ported box, has a box too big.
So sealed box becomes the only solution. Then you have far too high an F3 to blend with an unobtrusive sub, placed on an optimal position.
So that means you have to use two subs with the speakers on top. So you might just as well have made a two way speakers in the first place.
Now for small subs, you have two options, a small driver with very long throw, in a sealed enclosure , with lots of power and Eq. That is the approach of the Sunfire sub, designed by Bob Carver. For its size actually not a bad sub. Bob did have to tame it though, as early prototypes created a sonic boom!
The problem remains though, if used with a small speaker both speaker and sub would have to be in proximity, due to localization issues.
The other option for a small sub, is the coupled cavity approach, used by Bose. These have fallen out of favor for HT as a good one will not reach the 120 Hz required for the LFE signal. The problem is that you can have a nice low Q sub with a narrow bandwidth, or a sloppy high Q sub with a wide bandwidth. You can not have both!
So about an octave and half is about as far as you can stretch it. Bose goes way beyond that an still leaves a nasty gap between the bass module and satellites.
This is the typical Bose FR, which I'm sure many of you have seen before.
So in addition to the bass module not splicing with the satellites, even their small speakers are not very good. You can see that cone break up is occurring as early as 1200 Hz. There are far, far better small drivers around. It has been rumored for years that Bose will only spend around $2.0 dollars each for those drivers, and I can believe it.
So it is not a good system. It is designed to snare those who put form way above function.