RTiA9's, Denon 3312CI vs Marantz SR6006, amp?

[HAC2010]

Hello All

I?m new to the Polk forum (though not new to Polk) - I?m a big fan from the small RM series right on up to the top.
I have a question regarding a new setup I am in the middle of getting ?

L/R Polk RTiA9?s - purchased
Center: CSiA6 - scouting
Surrounds: FXiA4 - scouting
Sub: PSW404 (legacy from an RM setup)
AVR: Denon 3312CI ? scouting, but undecided vs Marantz SR6006

The room is approximately 18x16, so my questions are this ?

Is an external amp absolutely essential to drive these speakers - Does the Denon have enough juice (discrete 110WPC) without one?
Is there any justification in choosing the Marantz over the Denon (considering they are basically the same company now)
For surrounds, will the FXiA4?s be enough for the room?
Is the sub too antiquated for these components?

Any advice would be welcome ? I still have plenty of time to pull some triggers.

Thanks
HAC

[Lietuvis91]

The Denon puts out 125w, claims to have discrete amps, so this should be a pretty stout receiver for your purpose. Being the big speaker that the a9 is, it will definitely benefit from more power, but the Denon should do an ok job powering it.

[HAC2010]

Thanks, I may end up going without until I force myself down the road of separates - just wasn't sure if the A9's *required* an amp, or if it just elevated them to a next degree of performance.

Either that - or possibly get the XPA-3 - alot of people seem to like them here...with some exceptions naturally.

HAC

[PrazVT]

I was powering my A7s with a Denon 3311 for a while - it works, but dynamics and bass response will only come w/ a high current amp (ie. your next degree of performance).