DIY Guitar Envelope Filter

Envelope filters typically come in a standard pedal housing.

An envelope filter is a type of modulation effect, similar to a "wah" pedal but distinct in that frequency curve is pre-determined, rather than determined by the position of a rocker pedal. It processes the signal of the guitar to create a range of frequency modulations. Depending on the parameter settings that you choose, it can create a range of sounds from broad frequency sweeps to short, intense "fluttering" sounds. By building your own pedal, you save money and have a greater scope for customization.

Things You'll Need

• Pedal chassis
• Blank circuit board
• AC adapter jack
• 2 1/4-inch stereo jacks
• Resistors
• Capacitors
• IC chips
• Diodes
• Battery snap
• 9-volt battery
• Dials

Instructions

1. Clean the tip of the soldering iron with a damp sponge. Turn on the soldering iron.

2. Place the blank circuit board face-up. Push each board-mounted component into the relevant turret on the board. On pre-drilled boards, only the correct part will fit into the turret. Start with the diodes, then add the the resistors, IC chips and capacitors. Push each part into the turret so that the connector pins poke through to the base of the board.

3. Place the populated board face-down. Gently push each connect pin down onto the metal conductor strip.

4. Put a small amount of solder on the tip of the soldering iron. Press the tip against the connector pin and conductor strip simultaneously to fuse the board-mounted component to the circuit board. Repeat this process for each pin on each component.

5. Mount the jacks onto the pre-drilled holes on each side of the chassis. Slot them in and tighten the washer on the outside to hold them firm.

6. Mount the potentiometers onto the top of the chassis. Slot the base of each potentiometer into the pre-drilled hole on chassis.

7. Glue the battery snap to the base of the board, above the circuit board. Solder the red wire that is attached to the battery snap to the positive terminal. Solder the black wire to the negative terminal.

8. Cut four pieces of power wire with wire cutters. Trim the tip of each wire so that the metal is exposed. This makes it easier to solder.

9. Place the top of the chassis next to the base so that the wire between the potentiometer and the board can reach.

10. Solder a piece of wire to the output terminal of each jack and each potentiometer. Solder the input jack wire to the "Jack" eyelet on the bottom left of the board. Solder the output jack wire to the "Jack" eyelet on the bottom right of the board. Solder the potentiometer wires to the corresponding eyelet on the board. Each eyelet is marked with a code that corresponds to the part on the board. For example, the eyelet to which you wire "Output 1" of the "Range" potentiometer is marked "R1."

11. Fit a 9-volt battery to the battery snap.

12. Screw the top of the chassis onto the base.

Tips & Warnings

• Only solder in a well-ventilated environment.

References

• Build Your Own Clone: Filter 440
• Build Your Own Clone: Envelope Filter Kit Instructions
• The Electronics Club: John Hewes, 2010, Soldering Guide