I own a '72 1987 and '76 1987. Both amps had a pre phase master installed before I got them, but since I use a Fryette PS100 I don't use them, I leave them on max at all times.
I know both amps are not stock circuit wise and have had a few changes but I am not 100% clear on what changed and their tonal effects.
I do know that the '76 has an added tube effects loop which is what the breadboard is for, but otherwise seems to be pretty original circuit wise. Although it looks like the bright cap is missing?.
The '72 also has a replaced power transformer. It was replaced with a early 80's Drake from a JCM 800.
Here is what I'm trying to figure out:
the '72 is a lot more aggressive and has tons more gain than the '76. There pretty much is no cleans on the '72, it starts to break up a lot even at 2-3 on the high treble volume. Both with single coils and humbuckers. The '72 even has more gain than my 2203 which is weird to me because I always assumed 2203's had more gain.
The '76 doesn't start to break up until about 5, and you need humbuckers to do it. Until then it is pretty clean, it doesn't really get super distorted until you get to about 8 on the volume.
I mean it when I say that the '72 on a volume of 3 has about equal gain to the '76 on 7-8, especially with humbuckers. This is with the master volumes on both amps on max.
I'm not really complaining as some of my favorite Marshall tones are 80's hard rock like EVH, Lynch, Dimartini.
the '72 on a volume of 4-5 or more is already at 80's hair metal gain to me, both on single coils and humbuckers.
I'm trying to figure out why this is, and what the '72 has in it's circuit that is different than the '76 to make this happen. Is it the bright cap?
I want to know for learning purposes. If I ever got another vintage marshall in the future and I wanted to replicate the gain of the '72.
I consider my '72 to be a "magic marshall" because of this behavior.
Here are the gut shots of both:
1976:
1972:
I know both amps are not stock circuit wise and have had a few changes but I am not 100% clear on what changed and their tonal effects.
I do know that the '76 has an added tube effects loop which is what the breadboard is for, but otherwise seems to be pretty original circuit wise. Although it looks like the bright cap is missing?.
The '72 also has a replaced power transformer. It was replaced with a early 80's Drake from a JCM 800.
Here is what I'm trying to figure out:
the '72 is a lot more aggressive and has tons more gain than the '76. There pretty much is no cleans on the '72, it starts to break up a lot even at 2-3 on the high treble volume. Both with single coils and humbuckers. The '72 even has more gain than my 2203 which is weird to me because I always assumed 2203's had more gain.
The '76 doesn't start to break up until about 5, and you need humbuckers to do it. Until then it is pretty clean, it doesn't really get super distorted until you get to about 8 on the volume.
I mean it when I say that the '72 on a volume of 3 has about equal gain to the '76 on 7-8, especially with humbuckers. This is with the master volumes on both amps on max.
I'm not really complaining as some of my favorite Marshall tones are 80's hard rock like EVH, Lynch, Dimartini.
the '72 on a volume of 4-5 or more is already at 80's hair metal gain to me, both on single coils and humbuckers.
I'm trying to figure out why this is, and what the '72 has in it's circuit that is different than the '76 to make this happen. Is it the bright cap?
I want to know for learning purposes. If I ever got another vintage marshall in the future and I wanted to replicate the gain of the '72.
I consider my '72 to be a "magic marshall" because of this behavior.
Here are the gut shots of both:
1976:
1972:
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