SignalForm — Open Source Hi-Fi Bluetooth Boombox

SignalForm was supposed to be a crowdfunded hi-fi Bluetooth boombox. It got featured by Bambu Lab. Then it didn't fund.

23 people backed it anyway. That meant something.

Instead of letting it sit in my files I'm releasing the whole thing — print files, BOM, full assembly guide, CAD source — free for anyone to build, remix, and sell with attribution. This is what open source is for.

What it is: A 3D-printed stereo boombox built around one idea. Simple electricity. No apps. No Wi-Fi. No cloud pairing. Dual 4" aluminum full-range drivers, passive radiators for real bass, a Dayton Audio KABD-250 amp board with Bluetooth 5.0 aptX HD, and a 21V rechargeable 18650 battery system. Tactile knobs. A power button that clicks. Sound that surprises people.

Printed in PETG. Assembled with epoxy, silicone, and patience.

What's included:

• 3MF print files (Bambu Studio, tested on X1C and P1S)
• Full bill of materials with part numbers and sources
• Step-by-step assembly guide including wiring, sealing, and first power on
• CAD source files (.STEP) for remixing
• CC BY 4.0 license — build it, sell it, make it better. Put my name on it.

Full source, assembly guide, and community on GitHub: 👉 github.com/PrintedPulse/signalform

Build cost: ~$160 in components

If you build one, post it. If you improve it, share it. That's the whole point.

SignalForm is a Printed Pulse open source project by Eric Brunner. MakerWorld: @ericbrunner | Instagram: @printedpulse