Projects / Piano Circuit Machine
Piano Circuit Machine
Build a birch plywood key bed with eight tactile switches that drive Arduino inputs and play piezo / speaker tones. Optional LED per key. Learn frequency ↔ pitch and how a switch completes a circuit.
$9 Circuits
Digital guide + cut files + BOM + code · Parts sourced separately · Ages 8–14 with adult help
Keys8 tactile switches
OutputPiezo / speaker
Structure3mm birch key bed
ControllerArduino
Build time3–5 hours
Skill levelBeginner–intermediate
Pack contents
- 3-layer birch key bed SVG cut files
- Build guide: cut keys, wire, tune
- First-principles: frequency, circuits, musical math
- tone() firmware for a C-major scale
- Verified BOM (~$23–65 hardware; $15–40 with your own Arduino)
Typical hardware cost
Default structure is laser-cut birch plywood with real fasteners and hobby electronics you can source—honest BOM, not mystery modules.
- ~$23–65 ($15–40 with your own Arduino) in typical parts (makerspace cut toward the low end; mail-order toward the high end)
- Digital pack price ≠ hardware
The $9 pack is the digital guide + cut files + BOM + lessons + code, plus printable Builder's Corner build journal pages. Hardware is sourced separately — see Where to get kit materials. Buy with Stripe is live below.
Questions? Email us at lance.haney@gmail.com.
Pricing
- Home / Personal license $9
- Classroom license $35 — 1 teacher, up to 30 studentsOne $35 Classroom license covers one group of up to 30 students. Each additional group needs another license.
- Build materials available at cost + 10% — email for a quote
Learning outcomes
- Map switch closures to digital inputs with pull-ups
- Use tone() / frequency tables for a musical scale
- Explain Hz ↔ pitch and octave doubling
- Optional: light an LED with the same key press