This Just Might be the World’s Smallest Bluetooth Speaker with a Functional LED

Gadget Industry wanted to build the world’s smallest Bluetooth speaker, so they began by disassembling a regular module to see how small they could make things. To begin, they ripped the antenna directly off a 3W Bluetooth amp module, then had to rebuild the entire thing by hand after stacking the components. This small electronics stack is slapped onto the back of an 18mm x 14mm 3W speaker driver. A TP4056 charging module received the same treatment, being disassembled and reassembled to fit the small space required.

A little 60mAh LiPo battery powers the circuitry, and there’s even a power button to turn it on and off. The case is made from an epoxy resin that you pour on a sheet, let dry, sand down to give it a hazy finish, then cut into tiny little pieces and put them into a small cube to form the enclosure. Then you drill some holes for the speaker output and shove the electronics in. There is no total dimension specified, but simply looking at the speaker driver (18x14mm) reveals that this device is so little that it can sit on your desk or sneak into tight corners unnoticed.

Its sound is adequate for a Bluetooth speaker; simply stream music from a phone nearby, and everything works perfectly. Assembling it, however, is a completely different story; you must be familiar with a soldering iron in order to complete the desoldering, cutting, stacking, and rewiring process. Because you’re taking conventional modules that are already too large and attempting to squeeze them into microscopic tiny shape, you’re basically cutting corners.

Despite this, this build stands out because it is so hands-on, as Gadget Industry demonstrates how far common parts can be pushed when it comes to shrinking anything down to size. The resin casing provides a cool frosted appearance to what would otherwise be a basic 3D printed box.
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