Why do the 800's sound so different than the older super leads then? I thought the 800's have a different diode clipping section or something...Marshall Freak":fsd7pvlt said:
glassjaw7":ih64n6oj said:
Ah, I see. I'm not going to pretend that I know jack about Marshall circuits!Marshall Freak":ru5xfa1d said:
Thanks for clarifying. 
One of the main things to remember is that JMP, JCM 800, JCM 900, etc don't really mean too much, other than define the era they came from. JTM's were the earliest amps, and were a bit different, kind of an experimental time, with two transformers, tube rectifiers etc. Then the JMP, JCM 800, JCM 900, JCM 2000. All had different models in the "Eras" and the model number is what you need to pay attention to.
FourT6and2":1be5deuw said:
steve_k":3ad7uffm said:
My 1959RR will distort on 1 on the stock channel with a heavy handed touch...by 5-6 it's not much louder, just gainier and more compressed. I actually like that channel better than the cascaded gain of the second channel. What???Vrad":3qhn00xa said:The 1959 needs to have the volume on about 5-6 before it starts to distort. By that point, you're deaf! LOL!
Marshall Freak":26t2f6u1 said:Here's a kind of a generic timeline.
Late 60s early 70's Marshalls main amp was the 1959 Super Lead. In '76, Marshall modded it, and add a master volume, and a gain stage. Not a tube, but utilized an unused gain stage in one of the tubes and called it the 2203. They were the JMP 1959 (100 watt) and 1987 (50 watt) non master heads, and 2203 (100 watt) and 2204 (50 watt) master volume heads..
In '82, their contract ended with the Rose company, who was a financer, and it wasn't a good relationship for the most part, and in order to break away and start a new era they cosmetically changed things over to the "JCM 800" series.
They didn't change the models or numbers, so they're still the 1959/1987 and 2203/2204 heads. They also had combo amps, and other amps, which all had different model numbers. As well as the 2210/2205 Channel switching JCM 800's. The 900's had their numbers as well, the 2100, 2500, (SL-X and Mark III) 4100, 4500 (.Dual Reverbs) as well as the combos. The JCM 2000's had the DSL 100 and TSL 100 etc.
So, yes, the JCM 800 2203 is the "Same" as the JMP 2203 circuit wise, although different components along the way, changed the way they sounded to some degree over the years.
steve_k":26t2f6u1 said:
steve_k":aqtp9ri4 said:
FourT6and2":3oh0tx1a said:Awesome, thanks!
So, there is a 1959 JMP (4 input, 100 watt) with cascaded gain stages out there, non master volume? If so, is the only difference between it an a normal 1959 Super Lead the cascaded gain stage?
mmorse":1k5gsq3o said:
mmorse":2bajakmc said:FourT6and2":2bajakmc said:Awesome, thanks!
So, there is a 1959 JMP (4 input, 100 watt) with cascaded gain stages out there, non master volume? If so, is the only difference between it an a normal 1959 Super Lead the cascaded gain stage?
No. 100 watt cascaded JMPs are MV amps (2203). The 50 watt version is a 2204. The 50 watters remained pretty consistent between JMP and JCM. The JCMs had different cosmetics and switched from chassis mounted pots (vertical inputs) to pcb mount (horizontal inputs) in '84 to save build cost.
The 100 watters got the same cost cutting treatment AND they changed the filtering from 6 caps to 5 caps briefly and then to three caps. That change thinned out the tone of the 2203s that many people didn't like. That's how the whole vertical input vs horizontal input argument got started.
peterc52":14g1pdkn said:mmorse":14g1pdkn said:
I have a JMP 2204 from '83.
