Denon Receivers 1905, 2105, 2805 Further questions

[hershon]

I went to Ken Crane's today to hear their Denon Receivers and my results were mixed as to be honest my tentative but unsure conclusions are based on too many variables that I don't have any confidence in myself to make a decision on as the conditions were not uniform, so I'm asking for any help out there. I should add, that the sound quality was not a night and day difference between my current JVC RX-DV31SL 500 watts DVD receiver, but it was an improvement. Before I go on, I went to the Denon Web site and am totally confused as they have 2 different listings for receivers- one under (Home Theater Systems) Home Theater Series A/V receivers and the other under (Home Audio) Dolby Digital, DTS & THX A/V Receivers. What is the difference? Do the home audio ones AVR-2105 for example also need a seperate AMP or something or are they built in?

Assuming the Amp's are built in, because of a combination of different speakers with each denon model, different DVD players and the salesman I think playing them under different settings instead of the same setting that I wanted, I actually preferred the sound of the 1905 which to me sounded richer to the 2105 and the 2105 to the 2805. I played the Beatles "Norwegian Wood" on each system. I also listened to a Yamaha set up that I wasn't wild about, again possibly because the salesman didn't have it on the right settings. The one thing the salesman concluded was that my preference was to a bright sound, which oddly enough a recording engineer said the same thing, when he heard my home set up. Given that, should I go with the 1905 over the 2105 over the 2805, or should I trust the salesman who said for the money the 2105 is a better deal that will give me better sound. I play my system though Orb speakers & subs. Any help appreciated if this doesn't sound too confusing to you.