Build this simple 2 band tone control Circuit using transistor with complete schematic and layout you can download.
Tone Control Circuit
Last time I posted a 2 band tone control project that used an opamp IC here.
This circuit uses a transistor instead of an IC. This design is based on my previous post here but I haven’t designed the PCB for it. The tone control design was for “Super Bass tone control” which has up to 16dB of bass gain.
The circuit is stereo so you do not need to build 2.
Simulation
I used LTSpice for simulating this circuit. A bit of a challenge in using this simulation circuit is the lack of a potentiometer model.
As you can see on the simulation, it can boost 100hz bass frequency up to 16dB. You can further improve the bass frequency response by playing on the value of C5 and R8 on the simulation circuit.
PCB layout design
I used kicad for the PCB layout. I used 1 layer PCB so it will be easy to build
3D Render
The reason why I love to use KiCad is because it have built in 3d viewer and it is free. 🙂
Downloads
You can download the PCB files on the download page. I only include the PDF file on the downloads. If you need the kicad file, you need to subscribe to my youtube channel first and send me a message through my facebook page.
Bill of material
Ref | Value | |
C1 | 1u | electrolytic capacitor 25v |
C2 | 1u | electrolytic capacitor 25v |
C3 | 100u | electrolytic capacitor 25v |
C5 | 1u | electrolytic capacitor 25v |
C6 | 1u | electrolytic capacitor 25v |
C7 | 0.01u | ceramic or mylar capacitor |
C8 | 0.1u | ceramic or mylar capacitor |
C9 | 0.01u | ceramic or mylar capacitor |
C10 | 0.1u | ceramic or mylar capacitor |
C11 | 0.0022u | ceramic or mylar capacitor |
C12 | 0.01u | ceramic or mylar capacitor |
C13 | 0.0022u | ceramic or mylar capacitor |
C14 | 0.01u | ceramic or mylar capacitor |
C15 | 10u | ceramic or mylar capacitor |
C17 | 0.1u | ceramic or mylar capacitor |
C18 | 0.1u | ceramic or mylar capacitor |
C19 | 1u | electrolytic capacitor 25v |
C20 | 1u | electrolytic capacitor 25v |
C21 | 100u | electrolytic capacitor 25v |
J1 | input | 3pin JST connector |
J2 | VDC | 2pin JST connector |
J3 | output | 3pin JST connector |
Q1 | 2N3904 | NPN Transistor |
Q2 | 2N3904 | NPN Transistor |
Q3 | 2N3904 | NPN Transistor |
Q4 | 2N3904 | NPN Transistor |
R1 | 560k | 1/4W resistor |
R2 | 560k | 1/4W resistor |
R3 | 5.6k | 1/4W resistor |
R4 | 330 | 1/4W resistor |
R5 | 5.6k | 1/4W resistor |
R6 | 330 | 1/4W resistor |
R7 | 15k | 1/4W resistor |
R8 | 1k | 1/4W resistor |
R9 | 15k | 1/4W resistor |
R10 | 1k | 1/4W resistor |
R11 | 10k | 1/4W resistor |
R12 | 10k | 1/4W resistor |
R13 | 10k | 1/4W resistor |
R14 | 10k | 1/4W resistor |
R15 | 10k | 1/4W resistor |
R17 | 10k | 1/4W resistor |
R19 | 560k | 1/4W resistor |
R20 | 560k | 1/4W resistor |
R21 | 10k | 1/4W resistor |
R22 | 10k | 1/4W resistor |
R23 | 1k | 1/4W resistor |
R24 | 560k | 1/4W resistor |
R25 | 560k | 1/4W resistor |
RV1 | 100k | Stereo Potentiometer |
RV2 | 100k | Stereo Potentiometer |
RV3 | 100k | Stereo Potentiometer |