At the end of the day, I expect this loco to sound like my JLC Legacy Big Boy and the first VL Challenger. I don't want it to sound like my 844 or my TMCC Mallet that was only "two chuffs".
I doesn't even matter what is technically correct, per se....although that is certainly important. What does matter is this model be DIFFERENT sounding than most of my non-articulated steamers.
Personally, I like the sound "offset" below speed step 14 or so.