Which AV Receiver?


Hi,

I have a pair of Klipsch RP-8000F floorstanding speakers.
I am a little unclear about what I need to complete my setup.
I want to use these as home theatre speakers when watching Netflix or Satellite TV, and also as music speakers when playing off Spotify through the TV or via iPhone. 

The guys in the Amp forum recommended an AV Receiver but I don’t know anything about AV Receivers.
Are they able to power the speakers and bring out the best in them? I heard Denon, Onkyo, Marantz, are all good brands. Perhaps you can suggest a few models ranging from 300-1000 in price. 

I need enough channels to add in a sub (I have Klipsch R-12SW) and potentially a center speaker (yet to buy but probably will get the Klipsch RP-504C) at a later stage. 
I am a newbie to all of this so willing to learn, please forgive my lack of knowledge.

If you need more information please let me know. 
Many thanks in advance!
laher
Post removed 
Yes, amp in 758 is class A/B, so I would disregard my previous suggestion that it may be brighter than ideal, as that was based on an incorrect assumption that the 758 may use same class D amps as later NAD amplifiers.

That's not to say the 758 may not be bright, but if it is it won't be for the reason I suspected.

I cannot find any information on which dac is used in the 758.

Yes, there are newer marantz models.  Here's how marantz model numbering works:
7xxx is better than 6xxx which is better than 5xxx

As to the last two numbers, 
14 means current year
13 means 1-2 years ago
12 means 2-3 years ago
11 means 3-4 years ago

They don't always rev each line each year - for example, 7013 is most current in that line, while they have 6014 and 5014 out already, but 8012 is the last model in the 8xxx line.
The Marantz receivers would only be recommended if you want a warmer sound with rolled off highs.  The NAD would ultimately do better for HT clarity and excitement.  Your klipsch speakers are not necessarily bright.   But, like I said, also look at Arcam.  The Arcam is a type of Class A amp and will have excellent sound quality, but will have a very smooth and slightly liquids sonic signature.
Save a little more money and grab a Anthem MRX520, no other brand comes close to their room correction software and it's full featured. 
You won't go wrong with Marantz or Denon for HT, as they pair well with Klipsch. I would suggest going to the Klipsch forum with you question(s)and reading the forums, you'll get a hockey sock full of information there. 

cheers, and Happy Thanksgiving to our southern neighbours.