Build a MIDI Thru Box with Arduino Uno – Split One MIDI Signal into Three Isolated Outputs

Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.

Musicians, producers, and synth enthusiasts often face a problem: too many MIDI devices and only one master output. This kit lets you build a reliable MIDI splitter that takes a single MIDI input and fans it out to three independent, optically isolated outputs. No more daisy-chaining, no ground loop hum, and no latency. It's the perfect tool for live rigs, home studios, and classroom music tech labs.

What You'll Build

You'll solder a MIDI Thru box using an Arduino Uno as the controller and three 6N138 optocouplers to electrically isolate each output. The result is a robust, low-latency signal splitter that takes one MIDI In and provides three identical MIDI Outs, each driven by its own optocoupler circuit. Enclose it in a project box (not included) and you have a permanent piece of studio gear that rivals commercial units costing several times more.

What You'll Learn

• How MIDI current-loop transmission works and why optocouplers are essential for galvanic isolation
• Reading and forwarding serial MIDI data with Arduino Uno without altering timing
• Designing and soldering a multi-output splitter circuit on prototype board
• Debugging digital audio interfaces and verifying signal integrity with a simple continuity tester

Kit Contents

Why Buy This Kit Instead of Sourcing Parts Separately

Who This Kit Is For

This intermediate kit is ideal for CBSE Class 11–12 students working on music or audio-electronics projects, B.Tech ECE/EEE undergraduates exploring digital communication protocols, and participants in Smart India Hackathon building accessible music tech. It also fits well in ATL Tinkering Labs and college maker spaces like those at IIT, NIT, VIT, and BITS where students prototype performance gear. If you're a hobbyist musician who wants to expand a synth setup without breaking the bank, this is built for you.

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.

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.