New/Used Amp recommendations for about $3k-$4k?

What about the Parasound Halo A21+?

What about the Bryston 4B3?

I like John Curl’s design criteria and circuit topography over Bryston.
I would prefer 2 x used JC1’s over a new A21+ for similar money. Then if you can get a cheaper used A21+ for even less ??? but there’s no high Class-A bias switch like on the JC1’s and that’s a BIG + for me for serious listening.
They also have switchable input sensitivity from 50mV to 250mv perfect for unity gain active preamps or passives pre’s, like the Schiit Freya and Freya+ that have all basses covered passive, tube, or solid state.

Cheers George

Formerly owned the Bryston 4B3. Very respectable and versatile amp. Did a total system swap for my current BAT hardware including VK-255SE (best SS amp I ever owned). BAT VK for sale here at a negotiable $4500.

I wouldn’t suggest using a prepro with a good amp as it’ll just be a bottleneck to your overall system performance.  Just my $0.02.  Best of luck. 

no idea what improvement is possible over the emotiva’s you mentioned, as i have never heard them

in the price range (roughly) you mention, used, i would personally lean towards a hegel h20, or if less watts is needed, a pass or first watt amp

these are exceptionally good yet affordable solid state power amps

the benchmark amplifier is well known for its very clean detailed (if slightly lean) sound

I don’t think the monster preamp as mention above is a bottleneck because I’ve heard these speakers on the same preamp with the XPR-1 mono blocks and they sounded so sweet and detailed. 
I’m looking for an amp with as much detail as the XPR-1’s but don’t have the big form factor. I had to keep the XPR’s out on the floor on granite because they were monster sized amps and weight over 100lbs. 

My 8805 has a very nice 2 channel setup feature that allows for some nice 2 channel stereo listening. It’s not just a movie preamp. 
I have the same four sub woofers in each corner of my room for lost of bass.