Klipsch lascala subwoofer?

I have an extra Lascala, I was wondering if any one had ever thought to put a subwoofer in the base bin and use it as a subwoofer in addition to a pair of Lascals. If so, which speaker would some one recommend?
The cabinet design of the LaScala does not provide horn loading down into the subwoofer region; it is much too small to be effective at those wavelengths. Instead, the cabinet would act like a very small sealed box, of whatever internal volume is in the airspace behind the woofer cone.

If you insist on forging ahead, plan on using a great deal of EQ to get any kind of deep bass. So you'd want the subwoofer driver with the highest thermal power handling you can afford, making sure its magnet will fit into the available space, and plan to EQ the snot out of it.

But I don't think it's a good idea.

All you need is 1 good sub and it can be placed out of the way with a long interconnect. That is the best way if you want to augment the bottom end which it does not have. Remember bass notes are not directional. I hope I said that correct. I have 2 Dali Suite 1.2 subs 12" acoustic suspension types that I used with my Cornwalls. Well to be honest the Cornwalls didn't need the subs but one day I left them on and the Classical kettle drums shook the room. I enjoyed that extra bottom end. So especially when I listened to Classical I left the subs on.
There is another route you can go. It is definately a big enough box to convert into a subwoofer. After all, the internal volume of your speaker is bigger than most subs out there. You would remove everything that is inside it and turn it into an empty box. Give it some extra bracing inside, build a new motor board and install a 15" or even an 18" sub driver. Over at AVS, there is a DIY thread devoted to building speakers and subs. They can steer you to the right equipment and info needed to make a great sub out of your Lascala.
I really appreciate all the ideas and help, as I am a novice audiophile. I wanted to try and save the cabinet intact , for resale down the road. What I was thinking about now, was removing the base and maybe building a ported riser to allow air to move out, however not knowing much about acoustics, I did not know if it would be worth messing with it. If it is better to just get a subwoofer that might be the route to take. Thanks again
Duke is correct with his assessment. FYI : The Klipsch forum site has some good information on modifying the cabinets to improve the performance of the Lascala speaker. I have accomplished a lower bass extension, but more importantly, eliminated the box resonances of the original Lascala design, which to these ears, have taken a good design and has now made them great. I have not heard better (more musical and natural) bass, and coherence, up into the lower mids, from anything else thus far (except for 1 or 2 particular Khorn set ups over the years). However, I still use a pair of powered subs for the last octave (sub region). Enjoy. MrD