Simple Stereo Amp
Summary
I am going to build a simple stereo amplifier. This amplifier will be able to play audio from a CD player, smartphone, TV, etc. on various speakers I have salvaged from broken electronics. I am excited to build this because I really enjoy listening to and making music but currently have some old cheap computer speakers, and this amplifier would have much higher sound quality.
Plan
- Receive parts
- Assemble and solder amplifier board (day 1-2)
- Test amplifier board (day 2)
- Assemble rest of circuit (day 3-7)
- Drill holes in case (day 8)
- Mount all items in case (day 9)
- Final assembly and testing (day 10)
Circuitry plan:
- DC jack + connected to power switch
- DC jack gnd connected to gnd
- Line in LR jacks + connected to input selector switch
- Input selector connected to volume control knob potentiometer
- Volume control potentiometer - one pole to ground, one pole to output, wiper to signal
- Output of volume control connected to amplifier
- +12V connected to amplifier +12V
- Speaker output terminals connected to amplifier speaker output
Physical plan:
- DC jack, input switch, speaker terminals, line in jacks, power switch, and volume control have hole drilled in the plastic box and screw/bolt mounted
- Heat sinks adhered to amplifier chip
- Amplifier mounted with screws in box
Budget
| Product | Supplier/Link | Cost |
|---|---|---|
| Project box case | https://www.amazon.com/dp/B0B5QG83RC/ | $15.99 |
| Mounting screws | https://www.amazon.com/dp/B07ZH9GJWP/ | $11.99 |
| Power supply | https://www.amazon.com/dp/B07MXXXBV8/ | $20.99 |
| DC jack | https://www.amazon.com/dp/B07XSQP3CT/ | $4.88 |
| Input selector switch | https://www.amazon.com/dp/B07JM3M2B4/ | $13.49 |
| Speaker terminals | https://www.amazon.com/dp/B08YMZ88Z5/ | $6.39 |
| Amplifier board | https://www.amazon.com/dp/B08GYQTTXF/ | $21.99 |
| Heat sinks | https://www.amazon.com/dp/B09877J8RM/ | $3.75 |
| Line in jacks | https://www.amazon.com/dp/B07TY8XNRS/ | $5.99 |
| Power switch | https://www.amazon.com/dp/B07QQ21QQS/ | $6.99 |
| Volume control potentiometer | https://www.amazon.com/dp/B07DJ7H1YC/ | $9.99 |
| Soldering tools | N/A | Already have |
| Line in cables | N/A | Already have |
| Speakers | N/A | Already have |
| Subtotal | $121.87 | |
| Tax (8%) | $9.75 | |
| Shipping | Amazon Prime free shipping over $25 | $0 |
| Total | $131.62 |