This Electro Harmonix Big Muff Pi circuit would most likely be better making the change by a contemporary input-jack power and a DPDT bypass switch. The kinds of transistors and diodes are unknown. It really is most likely that any high acquire NPN transistor and diode 1N914 will work. Coupling capacitors marked with * have been reported at its greatest if it has altered to 0.1uF and also the capacitors marked with ** modified to one.0UF. The unique transistors had been labeled SPT 87-103, and diodes of origin are marked or 525GY or 523GY (hard to examine.)
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