Thank you for the comparison.
In terms of Beta 22 clarity and speed compared to the GS-X that is very helpful. The softening and some euphonic "warmth" for a lack of a better word; how does the Sigma/Beta 22 compare to one of the more neutral/transparent timbred tube amps like a Zana Deux SE?
My understanding among the tube amps that I am considering that in terms of timbre from neutral/transparent to warm and lush they are arranged in this order: EC ZD > DNA Stratus > WA22.
I am trying to understand the extent of the AMB's euphony?
(Bolded): you nailed it.
As for the second part, I have no experience with the ZD, Stratus or WA22. Sorry.