The Unofficial History of the Mesa/Boogie Mark Series

The clean channel on this is very nice, but some argue that EQ is needed on the lead channel to be able to dial the midrange out in order to get something other than the "Santana" tone. The IIA and IIB, and some late-model Mark I amps used a silicon device called "fetron" in place of one of the 12AX7 preamp tubes, and included a switch for ... ................
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