It’s an apples/oranges(but not Orange)thing. It doesn’t directly correspond, but the 200s(or Sorado, or Sonaro, they’re all the same head)is the theoretical counterpart to the Bassman, but rates as 60 watts via dual
KT88’s or 6550’s, is a linnear design, and features a tube rectifier. The later 190B was still the same amp basically, but with a solid state rectifier, and rated for a little more wattage. The classic Sunn head that would go against the Showman would be the 2000s, four power tubes at 120 watts, and a slightly different preamp/tone section. While there is only one channel on the Sunns, what you get is a lot more tuned in for bass, yet I find them hi-fi for what they are, and surprisingly bright(but in a good way). They were built from the ground up as a bass amp, not adapted guitar design, and coupled with the then forward-looking cab configuration couldn’t be beat in the tube realm until Ampeg upped their game, as far as US amps were concerned.
Just an aside…Sunn gear up through 1969 featured a woven, angled grill cloth pattern, whereas after, to the mid-70’s, it was a rectangular pattern similar to Fender, so don’t be surprised if the head and cab don’t quite match if you go with the 200s.
This is the difference, older on the right…
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