A few worms, yes.

GM is right, but that doesn't necessarily mean that you need to go out and start looking for a new receiver. Frankly, for the kind of money it costs to get a new unit with modern processing and even a decent amp stage you would be better at looking at seperates. If your current Denon has pre-outs you could probably benifit from a power amp connected through the "pre-outs", which would be a significant savings.

Celestion's bread-and-butter has always been their professional grade speakers for musical equipment. I'm not wholly sure that home applications are their niche. First and foremost I would recommend auditioning some new speaks. In your part of the world probably KEF, Wharfedale, maybe Dyneaudio and B&W. For the same kind of money that it would take to seriously upgrade the amp section in a decent new receiver you can get into an entry level or above set from any of these makers which, I believe, would yield a greater percentage of improvement.

Peace