What used amp should I pair with my newly acquired Monitor Audio GR60's?

At that price point I have found  the Jaton Operetta AV 5140 to be an excellent all-around performer.  I prefer a more detailed sound with sharper image focus/outlines and a tighter bass.  These Jatons are frequently available in 4 or 5 channels so you could use 1 amp to biamp your speakers, which is exactly what I did with very good results.  

Sonically, these amps are (for the price new) quite detailed and rather neutral though the bass may stand out a bit, not being exaggerated, but having more weight and slam than many I've heard.  I think power rating is 70w/8ohm  140/4ohm and has been plenty for me with several speakers with average efficiency even when played quite loudly.  

For what they sell for on the used market, I can't imagine you could do much better.  There is an upgraded 2 channel one on USAudiomart for only $300!   And in all honesty, I felt it bettered a Cambridge Audio 840W which I'd been using until I got the Jaton.  The Jaton was a bit more detailed and seemed more transparent.  Both are monsters in the bass department.  Appearance-wise, especially in pics, they do look like very little more than a small step up from some A/V receivers but in person, they are quite substantial.  For the money, I think you'll be very satisfied.

thanks.  I will look into it.  Someone else mentioned I should check this out:  https://www.usaudiomart.com/details/649730297-belles-soloist-5-amplifier-completely-refurbished-all-...

what do you think & how do you think it would compare to the other?
thanks. 

ring30----what amp did you settle on?

So, right now I'm using my Pioneer Elite VSX-52TX as a pre-amp.  Taking in the digital from either my PC or ChromeCast Audio.  Going pre-out to a Yamaha  RX-777 I picked up for $50 on Craigslist. I pulled the couplers on the Yamaha from between the pre-outs to the main-ins, and ran the pre-outs from the Pio to the main-ins on the Yam.  So I bypassed all the circuitry in the Yam & using the Pio to control the volume.  I also turned off all the speaker outputs on the Pio to reduce heat & other electrical interference as much as possible & running in direct mode on it (not sure if it makes a diff when running through the pre-outs on it).  It sounds great.  I still want to do some A/B comparisons. 

I also picked up a Denon 4311 just because it was dirt cheap around me.  Going to play with that also & try & compare.  Not sure it will be worth trying to do some bi-amping or try-amping with any of these configurations, but I thought I might try it with the Denon since my bi-amping zone 2 speaker outputs aren't working on my Pio.

Currently looking into an Emotiva UPA-200 someone is selling locally here for $175. Not sure if it's worth it or not yet.

Got any thoughts or opinions on any of that?
Thanks.

I had a pair of Emotiva XPA 1 gen II a while back very briefly.  I wanted the power for a pair of newly acquired BG Corp Radio 520 loudspeakers as I only had low powered tube amps at the time.  I could get moderate volume from a 45 watt push/pull EL34 based amp but obviously needed more.  The Emotivas really disappointed me.  I was able to compare them directly with a Theta Intrepid and Cambridge Audio 840W.  The Emotivas were quite lacking in inner detail with a rather flat 2D soundstage.  Image outlines weren't distinct and the bass was on the full side but lacked definition.  All this with some very good cabling and I did try them out on Meadowlark Herons (Hot Rod version) as well.  I have nothing but contempt for the Emotivas (though must admit I haven't heard their XRP line of amps).  Sorry for the harsh criticism but really, they are not worth the money and you can do soooo much better for less $$$.   

You have some really nice speakers according to the reviews I read on them.  I haven't heard that model but I thought the Silver 9i from many years ago was quite good.  Pretty much all receivers (especially their preamp section) are way below what those speakers deserve.  Of course, I don't know what qualities you are looking to showcase in your system so maybe I should inquire about that before I say much more.  What qualities are important to you in sound and which aren't quite so much?

Save your pennies on old average stuff and jump into the 21st Century with a GaN amp. I have not heard this one, but it should run circles around any of the old amps in your price range

https://premium-audio.com/gan-audio-amplifiers.html