Whoah, tone it down there, pard'ner. We might be able to help. As I read this post it looks like you have $1500 to spend on a new amp, sub and 2 more speakers?
Pogre: Going all western are we pard'ner? I'd like to see the mashup of the metal guy and the sequined Porter Wagner that comes out of that. My imagination often runs off on a tangent.
I hope your idea that there's 3 $500 buckets to spend is the correct one.
It would be a snug fit if otherwise.
The chief problem with the Denon 520 is that its a 2 channel integrated amp. Nothing wrong with the box, its a great box. But its a 2 channel setup.
When I see a request that says I want 4 speakers and a sub it always leaves me asking "for what?"
I remember another poster wanting 4 speakers. He didn't want a 5.1 multi channel setup for surround sound. No. He just wanted his music with 4 speakers. That thread went south in a hurry.
Jamie Jambo, the OP, could spring for any of the Denon mulitchannel AVRs that fit the budget if surround sound is the goal. The sub connection comes on just about every Denon AVR for sale today in the U.S.
Its literally a task of just getting a list of the Denons and picking one that has the features desired at the price point he wants. There's just about zero difference in audible output (maybe differences in Audessey capabilities). Or, you could recommend any number of the Marantz AVR's like you have. Great stuff.
To the OP: whatever subwoofer Pogre recommends, take that as a solid reference by someone who has killer subwoofers. Pogres subs are monstrous.
There are so many speakers to choose from, I'm going to just let that choice fall to the folks who really know that $500 a pair category. I'm just not the right guy for that.
Have some fun Jamie Jambo: buying new gear and setting it up is one of the most interesting tasks in audio. Listening is also pretty cool.