Marshall 100W Super Bass 1972 Black & Gold

Gary Moore's favourite amp was a 1972 Marshall Super Bass!

• Excellent working condition with less external wear-and-tear than you'd expect on a 44 year old workhorse.
• Purchased in 2000/2001 from David Angstrom (Hermano, Supafuzz, et al.)
• Used sparingly over the past 16 years but kept with TLC at all times.
• PLEASE NOTE: Tolex is peeling on ALL 8 corners.
• The letter D stamped in the back of the amp authenticates it is a true 1972. 
• This is the last year during which the turret boards were hand-drilled. Printed circuit boards were used thereafter. 
• Super Bass (pre JCM800) circuit is identical to the 1967 Marshall Super Lead, less the bright cap across the volume pot but this one has a cap in the first gain stage to add more bottom end.

THE METAL PANEL, HAND-WIRED ERA mid-1969 - 1973 (JMP Models)

During mid-year 1969, the gold Plexiglas front and back panels were dropped in favor of brushed gold aluminum panels; hence the term "Metal Panel" JMP. The electronic circuit design remained close to the original "Plexi" circuitry, and the amplifiers continued to be handwired through the middle of 1973.

Models offered included the Lead (50 watt), the Super Lead (100 watt), a Bass Model and PA Model. JMP 50 amplifiers were offered in both head and combo configurations, with and without Tremolo effect. The JMP 100 amplifiers were available only in the head configuration.

All of the handwired metal panel JMP 100 amplifiers and the majority of the JMP 50 amplifiers were of the "large" box variety. In general, the Marshall amplifiers became "brighter" sounding through the years. While the JMP 50watt electronic circuitry was similar to the JTM 45, the tone was quite different due; to the tuning of the circuit "brightness", the use of EL34 power amplifier tubes, solid state rectifier instead of a tube rectifier, and different electrical specifications for the both power and output transformers. Another key difference was the JMP 50 and JMP 100 amplifiers had a split biased preamp section for each channel, whereas the JTM 45 and JTM 100 had a common biased preamp section. This resulted in the JMP amplifiers having slightly different gain in the first preamp stage for each channel, whereas the JTM amplifiers had the same gain in the first preamp stage for each channel. Both the JTM and JMP amplifiers had one “bright” and one “dark” channel for added bass response.

The metal paneled JMP amplifiers were equipped with EL34 power tubes that provided the famous cranked up "Marshall Crunch". EL34 tubes are known for their compressed, tight, and mid-focused distortion, in comparison to the JTM amplifiers that were equipped with 6L6(5881/KT66) tubes that provided a more open and less heavy distortion. The JMP set the standards for hard rock tone.

In 1972, the Marshall Amplifiers that were sold in the US were equipped with the US made 6550 power tubes. The 6550 tubes offered their own unique tone which is often favored by metal style guitarists. However, most guitarists prefer the tone of the EL34 tubes over the 6550 tubes. Marshall amplifiers that were originally equipped with the 6550 tubes can be converted back for EL34 use.