AtmaSphere Upgrade from Mk 3.1 to Mk 3.3

I have a pair of MA-1 Silver Anniversary edition amps that I had upgraded to Mk 3.1 some time ago.  I see they are now up to Mk 3.III.  Has anyone made this upgrade?  What did you hear different, and how significant was it?

Showing 3 responses by gdnrbob

I only have experience with the 3.3's, but when I was looking at buying a non 3.3 Ralph and Adam have told me, it is a very big upgrade- sound and rebuild-wise(hence, the cost. If I recall, it also affect tube performance. 
Hopefully, others will chime in. I just want to give a quick response.
@honest1 ,
I am glad you posted your experience. I am also glad that you found it a significant upgrade.
BTW, did you get the Caddock Resistor upgrade?
Thanks for that info.
I really wish I had done it while it was in the shop.
Oh well, something to add to my upgrade list...