A large speaker in a comparatively small enclosure is not a good thing.

While lack of power may actually be an issue here to some degree, a lot of kabuki speakers I heard (and I heard a LOT in the service overseas) were remarkably deficient in real, deep bass for what one would expect from such a large woofer. They were overly heavy in the mid/upper bass (syrupy?) but down in the dungeons, they lacked big time.

FWIW, Kenwood made some pretty durn good receivers, assuming you use good speakers.