Ah.. Fender used to RULE, back in the 70s! I played the silverface bassman 10 combo in junior high school (the school owned it, along with the 74 P-bass they let me borrow for all of grade 9). "Played out" at some regional jazz band festivals and it was plenty loud and fat sounding.
Then in the Sr. high school jazz ensemble (in a different city) they had big Standell amps for the rhythm section at school, but when we went down to California for a tour - Oregon, L.A., Knott's Berry Farm, Escondido (Carvin Factory Tour!), and San Diego (grand finale on the Queen Mary Ballroom) - our "touring' backline was the same silverface Fender combos (4-10 for bass, twin for guitar, and the Rhodes piano had it's own suitcase amp).
When I finally got to the university jazz ensemble - it was a whole different story: the backline there was all
Orange (the older ones with the gigantic knobs, which I thought was
very cool... the only amps with bigger knobs than those were the Gibson LAB series, and some pretty rare Garnets)
By the early-80s,
every 50-watt bassman amp around our neck of the woods had been relegated to guitar duty, bass had moved on to the next level...