Both of these pedals have the 1S2473 diodes, But they differ in the 4558C (‘81) / 4558DD (‘84).
I don’t know guys, I can do a blind test and have my buddy exchange these two with my 2 newer MIT ones and I immediately can hear the difference, and the older ones sound better, I can hear it…
Now, Maybe I’ve just have 2 ‘lemon’ MIT’s, who knows.
1981 with 4558C
Extremely lightning FAST attack, very lively, bright and open, (Bright in a ‘good way’)
No Congestion, just lots of beautiful headroom.
No fog, no hesitation, the notes explode immediately. Sounds and feels massive!
Very tight bass.
More aggressive / tighter than the 1984 pedal.
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1984 with 4558DD
Very fat tone with slightly more gain, fantastic for lead playing.
Slightly slower attack. Maybe a touch more brown/fat than the 1981, but at the cost of less tightness.
A little ‘smoother’ / silkier / warmer / prettier than the 1981 pedal.
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