My “techs” never told me anything about Marshalls…I’ve been playing and gigging for about 40yrs. I still gig about 80 times a year. I have had so many Marshall’s I lost count.
My last 3-4 old ones needed caps, pots, and more and still didn’t perform consistently. Maybe I just got bad ones. The punch and authority was there, but they lacked sustain and fullness, or had weird frequencies going on.
My Morris amps and Suhr SL67 have been bullet proof and get me the tones I was hoping for in those old Marshalls. Maybe I’m deaf.
For actual reference of the tones i normally go for, here is my YT link. Mostly nonsense demo’ing gear I've borrowed or I’ve had for sale.
https://youtube.com/@jdzialak?si=6yg50alNJ0RdkqE7