Amp for VR4SR


I am looking for an amp to run my VR4SR.
My music is mainly vocal, strings and classic.
Has anyone checked VAC AVATAR vs UNISON RESEARCH - PREFORMANCE ?
Second hand will be just fine.
Budget is up to $5K- $6K
Would like to also hear about SS amp and or combination of Preamp + power amp - as long as it was checked Specifically with the VR4SR.
Thank you
128x128takeone
Since I am located about 10 hours flight from the US I assume that home trail will not be so simple to arrange....
and it seems there is no dealer around.
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I also use the Spectron Musician III SE MkII with the VR4SR MkII's. Results are excellent. Albert recommended this amp when I purchased the speakers and I appreciate his solid recommendation. I have not identified any weaknesses with this amplifier, a first for me. The praise for the Spectron is well deserved from my perspective. Speaker cables are Acoustic Zen Double Barrel and IC's are balanced FMS Zero's. Preamp is Audio Research Reference 3.
Thank you Mdrummer01 and Mmcghee
since this is a class D Amp, Did you also checked nuforce and/ or CIA?
Takeone: I have had both Nuforce 9SE and Channels Islands (D-200) in my system in the last couple of years. Without going into an extended assessment, my experience would be: Nuforce-Excellent and deep bass control, RFI can be problematic, especially if you have a tuner in your system, highs can have a glare but can be tamed with the right cabling. I've heard great things about the V2 upgrade...but haven't heard them myself. Channel Islands: Less bass authority but you can listen to them all day with little fatigue, no RFI issues, a pleasant personality but the goose-bump factor wasn't there. Last year at RMAF Albert was running a pair of 4jr's MKII (I beleive) with a new CI model D-400..twice the power of the D-200s...sounded wonderful. From my perspective, the Spectron takes all the best attributes of class D and a few of attributes of tubes and rolls them into one.