A good starting point would be Marshall Super Lead 100 serial number 10000 to 12000 year 1968
Start Jimmi Hendrix modded Super Lead 100 stock 56K resistor Hendrix and EVH amps 33K same as the JTM 45/100 1966
and the treble pot changed from 25K to 50K they both played their amps on 10
I own Marshall Super Tremolo 100 has the 33K resistor stock 50K treble pot was used to record Soundgarden super unknown
serial number 10412 ST it is my understanding Marshall just moved to the new factory and the 10K through 12K serial number amps
were made for less than 90 days I have never seen a 11,000 serial number Marshall ever.
Hendrix amp.
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Former Soundgarden amp
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