I tried using Scott 222C with a set of Harbeth Super HL5, previous model in the 5 series, and it was not a good combination. My recollection is that the 222C uses EL84’s and only put out 20 watts so this may not be relative to your setup.
For what it’s worth, I have not found any tube amp to sound good with any Harbeth speaker. I know lots of people like tubes with them and YMMV. I have owned the Super HL 5’s, the Monitor 40’s and now have the Super HL5+ and tried a number of tube amps with all of them and did not like the results at all. Again, this is only my opinion and only you can tell what you will like.
Good Luck!
For what it’s worth, I have not found any tube amp to sound good with any Harbeth speaker. I know lots of people like tubes with them and YMMV. I have owned the Super HL 5’s, the Monitor 40’s and now have the Super HL5+ and tried a number of tube amps with all of them and did not like the results at all. Again, this is only my opinion and only you can tell what you will like.
Good Luck!