An ENVELOPE FILTER project

Ah, the good old envelope filters, expressive little boxes of wah-wah goodness without the treadles. Basically, the envelope filter sweeps a certain range of boosted frequencies that is triggered by detected envelope of a string's initial attack. Pretty nifty.

The following is the Nurse Quacky project (which is a bit tweaked EHX/Dr. Q circuit). Original circuit by the good guys of Home-wrecker.

THE SCHEMATIC (click for larger image)

THE PCB [note: to use the pcb, right click on the pcb image and paste onto a blank Word sheet. Print a copy, and photocopy that print into a photopaper.]

THE PARTS AND LAYOUT (click for larger)

the parts list:

Part        Value         

C1          10nF          

C2          10nF          

C3          4.7nF         

C4          4.7nF

C5          100nF      

C6          22uF          

C7          47uF          

C8          100uF         

C9          1nF           

D1          LED5MM        

D2          LED5MM        

D3          IN4002         

IC1         LM358         

Q1          2N3904        

R1          47K           

R2          47K           

R3          470K         

R4          470K          

R5          47K           

R6          10K           

R7          3M3           

R8          51             

R9          220           

R10         470K          

R11         22K           

R12         27K           

R13         27K           

R14         100           

RANGE       B25K          

SENSITIVITY B100K         

ATTACK         B1K            



(this project is for personal use only. not for sale or commercial use. all rights reserved by the owner.)