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


I'm looking some new Paradigm Founder Series 100f speakers and would like to get rid of my Emotiva UPA-1 mono blocks for something else. 

I really like the form factor of these amps and have been very happy having them and they will make the next buyer happy also but I want some thing very detailed and clean. 

I just got rid of Emotiva XPR-1 mono blocks after hearing the 100f's on them and could absolutely hear the detail and cleanliness those amps had with these speakers. 

What do you think?
todd1010
I’m a bit confused, are you saying you want to get rid of the UPA-1’s after hearing the XPR-1’s? Or do you currently have the XPR-1 and looking for something else?
Also you didn’t mention what you are using as a pre amp but you may want to consider making an upgrade there first. Lack of detail and cleanliness as you put it could imply that your pre amp is stifling the performance. If the concern was more about bass & dynamics, then carry on with the power amp swap. Personally I’d first try a tube pre amp like the Schiit Freya to open things up before changing the amps.

Changing the power amp can also help with these things, but it may make less of a difference depending upon what you are using for the pre.
Yes after having the XPR-1’s in my system and going back to my UPA-1’s I want something else. 
I am using a Marantz 8805 preamp. 
I’m not interested in tube amps. 
Well there you go... a monster AV Preamp at the heart of your system and you aren’t satisfied w/ music performance. Let me guess, guitars could sound a bit meatier, brass a little brassier, vocals don’t have that holographic 3d realism, performer in the room with you type of thing. Maybe a few panes of glass could be in the way? If only there was a solution. Enjoy the SS amp merry-go-round.
todd1010 OP
I’m looking some new Paradigm Founder Series 100f speakers and would like to get rid of my Emotiva UPA-1 mono blocks for something else.
The 100F’s drop to 3ohms around 100hz, but!! are also -45 degrees phase angle there too, which means they could be as 1.5ohm EPDR load as seen by the amp.
https://www.soundstagenetwork.com/images/stories/loudspeakermeasurements/paradigm_founder_100f/imped...

https://www.soundstagenetwork.com/images/stories/loudspeakermeasurements/paradigm_founder_100f/elect...

If you want the very best out of them in that bass area, suggest an amp that won’t flinch at those kind of bass loadings.
My suggestion for your budget would be used John Curl’s Parasound Halo JC1 monoblocks. They can be switch to high bias sweet Class-A sound for serious listening. And low bias for other listening, rock or background.
https://www.stereophile.com/solidpoweramps/774/index.html

Cheers George