B and K Refernce 2220 Next Step

I am looking to upgrade this amp, does anyone have an opinion on where I can go from here for about 1k used or should I keep what I have for that price range? I am using the amp to power Sonus Faber Concertos (The bookshelfs) so I dont think I need a lot of power.

My system is a VPI scout with Granite 770FP preamp

Thanks, any input would be appreciated
you could spend around 1500 and get a yba, BEL, or belles, or other, but in my opinion, just keep the b&k. the improvements will most likely be minor even if you spend a few grand plus. the b&k never gets discussed much in these forums, but it is very good.
Because you asked, here is my two cents. One, buy more music and enjoy your present system it is very nice. Two, add perhaps Monarchy, or another class A amp to the list above. Three, perhaps you should make the move to tubes. Sometimes it is nice to try some new gear, if only for a change of pace and not overall sound quaility.
I sort of agree with Jaybo and Glenhifi, but if you really have the itch for a change, you may want to try tubes - and specifically a TAD 60. There's one listed currently (I have no affiliation), and they come up used now and then, or you may be able to get a new one directly from TAD. The difference you'll notice vs your B&K will be more holographic imaging. In my limited experience, the difference between B&K amps (ie in the class of your 2220) and other SS amps is more subtle, and not necessarily profoundly better.
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I like the idea for the tubes thanks for the suggestions. I do have a Vandersteen Sub 2wq which I enjoy bc the sonus fabers are a little light on the base.