Is the 6k unit a dedicated midrange?
I thought it was more of a mid-bass unit.

Funny you found the studio 'speakers coloured and the meridians neutral; I've not heard either so I'm not doubting you, just a little surprised as the ATC midrange is supposed to be one of, if not the best available.

I do like a dedicated midrange though, all down hill since the M1...🙂 😉