Single-channel 10W guitar practice amplifier based on the TDA2050
Here’s a quick demo, clean tone from a Spanish guitar with built-in pickup:
This is a 10W guitar practice amplifier circuit and was designed for the Fundamentals of Audio and Music Engineering: Part 1 Musical Sound & Electronics course offered by University of Rochester on Coursera.
The amplifier itself is designed to teach simple tone and distortion circuitry.
|R1 R3 R4||3||1 MΩ|
|R7 R14 R16||1||22 kΩ|
|￼C1 C4 C5 C11||4||1µF electrolytic|
|LED1||1||3mm Red LED|
|J1||1||12V power connector|
|J2||1||6.35mm mono socket|
Hardware and other parts:
- DIP8 IC socket (for the TL072)
- SPDT power switch
- 2.1mm power jack
- 12V DC power supply
- 1⁄4” Phono plug
Cabinet Design - TODO
Some reasonable dimensions:
- A well rounded frequency response translates to a cabinet volume of roughly 5832 cm^3, or interior dimensions of 18 cm x 18 cm x 18 cm.
- For a bass heavy amplifier, a cabinet volume of roughly 2754 cm^3 will work better. This corresponds to interior dimensions of 18cm x 18cm x 8.5cm.
Styrofoam board can be used for a quick build, but a wooden case will sound slightly better.
I’ve mounted mine in a wooden box of about 2700 cm^3 volume, with a removable rear panel so I can experiment with tone.
Sample oscilloscope trace:
- 12V power
- CH1: input (1kHz, 20mV sine)
- CH2: output, minimum gain & tone