Just for fun and to see if there is something wrong with your reciever, try setting your fronts to "large" and listen in pure direct.
If your receiver is working properly, there should be no way you aren't getting the same bass and spl as with the old vintage amp. The 3310 is a nice receiver, lots of power.
I followed your suggestion and it really seems to myself that the bass is lacking on my Denon. I will be getting a spl meter just to make sure the volume is matching .
As for now I am listening to music only on my vintage amp (2 channel mode, which sounds really good to my ears now). So the Denon is only being used to watch movies.
