Related to the #1987 and the #1959 respectively, they were designed for bass players. It’s 200W of pure loudness The Marshall Major 200w has a different circuit than its “little brothers”: the pre-amp has two ECC83s, but the third tube (the “driver tube”) is an ECC82 (a.k.a. Ritchie Blackmore was a famous user of the Major, but they were heavily modded at the Marshall factory (as said in an interview) and later by a man called John Dawk. These amps also CAN NOT TAKE ANY KIND OF BOOST OR OVERDRIVE. These amps would blow because they were already working at critical point without anything, so if you plugged something to make them run even hotter… This is one of the reasons why the Major was discontinued in 1974. Note: 8 knobs instead of 6 These amps had an extra 12ax7 tube for the “tremolo” effect.But many guitarrists also decided to try those and they found out that they could get really interesting tones with them. If you thought a Marshall Super Lead was already too loud. Blackmore’s amps had extra power tubes, making it even more powerful, as well as extra gain stages. They are easy to tell apart because the two extra knobs (“speed” and “intensity”) on the front panel.But Fil’s Metro is a reproduction of this very same amp, so you might be familiar with it by now.Please note the “Black Flag” JTM marking that was used at that time.
They can easily be converted into Lead circuits as well. For that reason, these amps are less expensive and are a really great deal (if in good condition, of course). Did I mention that Free used a lot of Marshall Super PAs on stage? On a side note, a faulty Marshall Super Lead #1959T was modified by Tim Caswell (he used the extra 12ax7 as another gain stage on the pre-amp), and it became the legendary #39 of SIR studios in California, USA.
You can end up buying something that is not what you expected or even something that is damaged or modded beyond repair.