Buchla-ish Envelope Follower

	A	B	C	D	E
1	RefDes	Value	Type	Quantity	Notes
2	C1	47n	Film 2.54mm	1
3	C2	4.7uF	Electrolytic 2mm	1	Fit on it's side after fitting Pot - see note on board.
4	C3	100pF	Ceramic COG/NPO	1
5	C4	1uF*	Film or Electrolytic 2mm or 5mm	1	This sets the speed of the envelope. Lower the value for faster response. The trade off is the lower the value the more ripple you get at low frequencies. I've used 68nF on my first build which does leave ripple at bass frequencies.
6	C5, C6	47uF	Electrolytic 2mm	2
7	C7	100n	Film 5.08mm	1
8	C8, C9, C10, C11, C13, C14	100nF	Ceramic 2.54mm	6
9	C12	10nF	Film 2.54mm	1
10	D1, D2, D3, D4, D5	1N4148		5
11	D6		3mm LED	1	Solder in place before fitting the jacks, the 2 way and 3 way headers. Insert the jacks without soldering to get the LED at the correct height to the panel.
12	J1, J2, J3, J5, J6, J7		Thonk Jack	1	Wire the switching pin to the 0V pin on the Pre In Jack - these are the 2 pins close together.
13	J4		Euro 10 Pin Power 2.54mm	1
14			5 pin header	1
15			5 pin socket	1
16			3 pin header	1
17			3 pin socket	1
18			2 pin header	1
19			2 pin socket	1
20	L1, L2	Ferrite Bead		2	Or 10-22R resistor
21	P1	50k Linear (B)	Alpha 9mm Pot Vertical	1
22	R1, R8, R18, R25, R26	1K		5
23	R2, R4	2M2		2
24	R3, R14, R20, R21, R29	100K		5
25	R5, R9, R13	470R		3
26	R6, R23, R27, R28	4K7		4
27	R7	620R		1
28	R10, R12	33K		2
29	R11, R19	10K		2
30	R15, R16, R17	470K		3
31	R22	1M		1
32	R30	6K8		1	Increase this value for a higher comparator threshold.
33	SW1	On/On	Switch SPDT 2.54mm	1
34	U1, U2, U3		TL072CN	3	U1 is pre-amp I've used a NE5532
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