Denon 3311 with 5.1 and zone 2 towers?

Ray,
Even though the BP's are rated at 90db, they can be described as power hungry. Your receiver should have more than enough power to run them though. The speakers rating is simply a maximum wattage rating.
The questions may come out of how you are running these speakers. Are you using 2 of the 7 channels for the second zone? Keep in mind that all 7 run off the same power supply and zone 2 may sound better/livelier when zone 1 is not in use.
The other issue is the zone 2 volume. Most receivers will have a built in limit on volume. You may need to adjust the max setting by 10db and see if there is a difference (assuming that's how it works).

I called Denon and they said that I can not adjust the volume on Zone 2 as they are concerned that Zone 1 and zone 2 will be driving too hard together and possibly burn up the amp. Is there a trick to adjusting the limit on the volume that you are aware of? I am using 2 of the 7 channels for the second zone. Any additional help would be appreciated Elevick.

Denon got cheap on us! You used to be able to go into the set up screen and set the level on zone 2 max to anywhere from -60db to 0db. I got rid of a Sony ES for that reason.

2 options I see: Using an impedance matching volume control on zone 2 would work. You can find them for $20 for a cheapo to $60 for a really good one.

The other option is to use the pre-amp outputs for zone 2 into an integrated amp. Not quite the same deal but it will work best.