Acoustic Guitar Fuzz on Breadboard

Warning !

This project was designed for use with Acoustic guitar , so note that It may not be suitable with Electric one.

About the project:

This simple Fuzz protoboard project consist from really simple but effective circuit. It's dedicated to add some slight fuzz which you could use to give some electric charachter to your playing. The components you need to use are very few and the result is impressive if we take in mind the low cost and simplicity to build.

Things you need:

1. Breadboard

2. NPN Transistor BC548 (This one have max gain of 800 but if you pick something with similar high hFE / Beta ( β ) will work also)

3. Two Resistors - 47kΩ and 4,7kΩ (Ratio: 10:1)

4. Two Capacitors - 47 μF , 16V , 85℃

5. Five Diodes 1N4007

6. One Silicon Zener Diode (Forward Bias - 6,5V)

7. 9V battery clip jack

8. 9V battery

9. Guitar with single coil pickup (if you don't have already you can build one. Here's a link to the project: https://www.instructables.com/id/Make-A-Guitar-Pi...

10. Power Amplifier or Pre-Amplifier from Audio Mixer (Note: You need to be careful with the potentiometers on the Amplifier or Pre-Amplifier because this way you could distort the sound as well , so watch on the LED audio meter to not going above 0 dB)

11. Male XLR microphone cable or TRS 6,3mm (1/4'') stereo jack (In case you'll use TRS cable , you need to add 1/4'' audio connectors on the output)

12. Jumper wires

The schema is really simple. It use only one single transistor which serve to amplify the signal received from the guitar pickup. First , we have the input from the guitar pickup (doesn't matter which pickup wire you take for hot , you only need to place one into ground). Then the hot pickup wire and the positive wire from the 9V battery meet on the same branch followed by electrolytic capacitor which goes to the base of the transistor and serve to remove any DC noise from the signal. The lower the value of the capacitor , the higher frequency signal noise will be removed and respectively the higher the value , the lower frequency noise will be removed. So this act like low-pass and high-pass filter next with the 10:1 ratio resistors - first the 47 kΩ resistor goes from the base into the collector and the 4,7 kΩ resistor goes from collector to ground. This form a voltage divider which can serve as ratio for amplification of the signal. Then the emitter goes to ground and the second capacitor goes from the collector to the anode of the first diode. Then we have configuration of another 5 diodes formatting diode clipping circuit , so every diode clips respectively the positive and negative tops of the sinusoidal signal which cause the signal to distort. At the end we have one zener diode which serve as voltage regulator. The anode of the zener goes to ground and the cathode takes the signal straight into the positive connection (in this case number 2. on the male XLR cable) then into the power amplifier or pre-amplifier or whatever you have. The negative and ground connections of the male XLR audio output connector - in this case 1. Ground and 3. Negative , goes into the negative side of the battery so that way it close the circuit.

Feel free to experiment and add different components if you're experienced enough.

Note: I would like to suggest you to use as less as possible jumper wires and to place the components as near as possible one to another. This way you'll avoid parasite capacitance , inductance and resistance which is important for more clear and noiseless sound as well for proper functions of the circuit.

The schema of the circuit could be found in the pdf file below.

As you can see , I don't have XLR audio connector for the output so I improvised with three metal rods. I suggest you to use audio connectors for safety purposes but in case you don't have you can do it that way. Do it at your own risk.

You can see the proper wiring of the inputs and output on the images above.

Enjoy ! If you like it don't forget to favorite this project !