The earlier model with 6550s in the poweramp had an autobias circuit which was (supposedly) a pain in the bum (my YBA200 has been modded to remove this). This was deleted for the YBA200-2. A 5751 would be a option for V1.
I have read very negative reviews of the head, but it wasn't clear whether the authors were au fait with the *complexities* of a passive tone stack, ie 'flat' is 2-10-2, if you run 'everything at noon' you are going to get a scooped tone for sure. Max out the mid control and use the range control to tune the frequency point. I like Range on minimum and the bass maxed out to give a gentle bass/low-mid boost. I found a schematic online and fed the values into the tone stack calculator -- to my great surprise/amusement it confirmed that that is exactly what my settings are doing. This seems to work well with the SVT212AV which rolls off below 70Hz. There is also Resonance which controls the overall 'tightness' -- off = 'modern' and maxed = 'vintage'. Turn it up and you get a pillowy, boomy effect and the notes really bloom. When I first had the head I maxed it but after a while it was just silly, so it's down at noon now. Into your 1822 at volume, you might want it off altogether.