Parasound A21 and A21+: Significant Improvements in SQ?

Also Is the new A21+ a John Curl update?

To me it wouldn’t matter, as those updates are just bigger, more, better things to do to it, everything has a monitory max to it, the A21+ has more build budget so it's got higher retail cost.
Most of the differences are just over engineering differences, hence the higher costs. But the basic topology of the circuit design is still John Curl’s, and that’s the heart and that’s what matters, the sound signature should be more similar than more different.

Cheers George

Thank you George.  What I'm looking for is refinement. 

Its not good that it now weighs 70+lbs. I'll have to think about that.

While there are many ways in which the Parasound line excels, even the Luxman integrateds can make them sound constrained and too warm sounding.

Depends very much on your speakers though, with B&W, Focal, Dali or GE I would imagine the Parasound is a better match.

The speakers I'm listening too the most are the B&W 705 S2 and the Elac Uni-Fi UB5. 

I am using a Class D Classe AMP2 or a Parasound A21.  The AMP2 seems fast and precise while at the same time a tad bright.  The A21 on the other hand is the opposite.  They are both very powerful and I like them both but I'd like to try a blend of the two.

Also, jdub39, you will find a comparison of the A21+ and the JC5 on Youtube. I expect I would like the JC5 but I'm not ready to drop $4K+ on an amp at this time.

I had an A21 then upgraded to the A21+. The + definitely had a bigger more refined sound to my ears. I’d say it was worth it. I then upgraded to the JC5. I’d say the JC5 had very little or no clear audible improvements over the A21+. 
I love Parasound products in general. But if I were doing it all over again, I’d get the 21+ and stick with it. Matched with a JC2 or I suspect many other preamps, and it is a beautiful sound.