70's ELECTRO HARMONIX DELUXE BIG MUFF  Large Metal Box 220V Excellent Conditions !

This Unit sounds great. Very clean example.2 controls for the compression section and 3 for the fuzz section.
Basically it's a big IC Big Muff with a Soul Preacher compressor included in its circuit! Powered exclusively by current.
It exists in the version with Blend switch (for de / select the stage of comp) [DBM1] and in the version series / parallel switch [DBM2] (we conventionally call them DBM1 DBM2). The series / parallel switch basically allows you to reconfigure the way the comp and distortion section is docked.
The first model with the Blend switch

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