Karplus-Strong String Synthesiser Kit with Arduino Due + LED
Build a 6-Voice Polyphonic Karplus-Strong String Synthesiser with Arduino Due
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
Create a six-voice polyphonic musical instrument that synthesises plucked string sounds using the Karplus-Strong physical model. This advanced kit leverages the 32-bit ARM Cortex-M3 of the Arduino Due, an MCP4725 12-bit DAC for pristine audio output, and touch-sensitive controls for expressive performance. Whether you’re a musician exploring generative soundscapes or an embedded systems developer diving into real-time signal processing, this project delivers a studio-grade synthesiser you can hold in your hands.
What You'll Build
A fully-functional polyphonic string synthesiser capable of playing up to six notes simultaneously. Each voice uses a Karplus-Strong waveguide model, controlled via two rotary encoders for pitch and timbre, with visual feedback on a 0.96-inch OLED display. Touch sensors on the MPR121 provide velocity-sensitive triggering, and the built-in PAM8403 amplifier drives a 3W speaker for immediate sound output. The entire system is housed in a custom enclosure, ready for performance or studio use.
What You'll Learn
- Implement the Karplus-Strong string synthesis algorithm in C++ on the Arduino Due
- Interface an I²C MCP4725 DAC for high-fidelity audio waveform generation
- Design touch-sensitive input with the MPR121 and map it to musical expression
- Manage real-time multitasking for polyphonic voice allocation and OLED display updates
Kit Contents
| Component | Quantity |
|---|---|
| Arduino Due | 1 |
| MCP4725 DAC | 1 |
| PAM8403 Amp | 1 |
| 3W 8Ω Speaker | 1 |
| MPR121 Touch | 1 |
| Rotary Encoder | 2 |
| 0.96in OLED | 1 |
| 10kΩ Resistors | 10 |
| 100nF Caps | 15 |
| PCB Prototype Board | 3 |
| Enclosure Box | 1 |
| 9V 1A PSU | 1 |
| Soldering Iron | 1 |
| Solder Wire | 1 |
Why Buy This Kit Instead of Sourcing Parts Separately
| Factor | Sourcing Separately | Compoden Kit |
|---|---|---|
| Compatibility checks | You verify every part | Pre-tested as a system |
| Build support | Forums and scattered tutorials | AI companion trained on this exact project |
| Time to first working build | Days of debugging | Hours, with step-by-step guidance |
| Shipping coordination | Multiple sellers, multiple delays | One shipment from Bengaluru in 3-5 days |
Who This Kit Is For
This kit is designed for electronics and audio enthusiasts with a solid foundation in Arduino programming and embedded systems. Final-year B.Tech ECE/EEE students working on signal processing projects will find it an impressive capstone demonstration. Hobbyists and DIY synthesiser builders, including those from maker communities at VIT, BITS, and NIT, will appreciate the pre-tested hardware and detailed build companion. It is also suitable for music technologists and researchers prototyping physical modelling instruments.
Built and Backed by Compoden
Every Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.
What if I get stuck during the build?
Our AI build companion is trained on this exact project—scan the QR code inside the box for step-by-step troubleshooting. You can also reach our team over WhatsApp for real-time support.
What is the Karplus-Strong algorithm?
It's a physical modelling technique that simulates string vibrations by feeding a short burst of noise through a filtered delay line, mimicking the decay of a plucked string. This kit implements a polyphonic version with six voices, each independently tunable.
Do I need prior experience with Arduino Due?
While the kit includes all components and the AI companion guides every wire and line of code, we recommend familiarity with Arduino IDE and basic C++. The Due's 84 MHz ARM processor requires careful power management and DMA for real-time audio, so intermediate to advanced programming skills are helpful.
Can I use this kit to create realistic guitar sounds?
Yes, by adjusting the filter and damping coefficients, you can emulate nylon-string guitar, harp, and even metallic plucks. The two rotary encoders let you morph timbre in real time, and you can program custom scales in the firmware for unique microtonal instruments.
Arduino Due implements Karplus-Strong physical string model for 6-voice polyphony via R2R DAC output.
What's in this kit
Choose your assembly option:
- Soldering Kit — 25W soldering iron, 60/40 solder wire, flux, and small perfboard for permanent assembly.
- Breadboard Combo — 800-point full-size breadboard with 65-piece jumper wire pack for solderless prototyping.
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Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items