My Lego hyper-fixation at the end of 2025 led me to my magnum opus: the Retro Lego Radio, transformed into a working bluetooth speaker. It was a fun build. This replica of a 1970s vintage radio currently lives on my desk because it’s a beautiful object to have on display.
I wanted to turn it into something actually useful. The Radio came with a block of pre-installed sound snippets — charming for kids but the novelty wore off fast.
My Plan for the Lego Speaker Build
The Lego Radio is designed to hold your phone or a small bluetooth speaker inside. I went a different route. I bought a simple bluetooth kit like this one. It’s advertised as a STEM Project for young kids (no soldering required). With a little fiddling, I managed to fit two speakers, the battery pack, and the on/off switch inside the body. For the audiophiles: the sound was not great as you can imagine. It’s best for listening to news or podcasts so I wonder how the acoustics can be improved but that seems like another deep dive into another hobby rabbit hole.
What I Would Change Next Time
A few things I will attempt to change or upgrade now that I’ve gone through this process:
-
I’m not a big fan of bluetooth, so my first upgrade would be adding an aux 3.5mm input. I’m not sure if this helps sound quality but it would be easier everyday use.
-
I’d also like to move away from four AA batteries toward something USB-powered, rechargeable, or even solar.
-
I had hoped to wire one of the existing buttons to toggle the speaker on and off, but that turned out to be beyond my scope — a project for someone with a more mechanical or engineering brain.
Overall, not bad for my first try. If you can help me figure out how to rig the buttons to turn on the speaker or if you want to share your own build or thoughts, feel free to send me an email.
And if anyone from the Lego company happens to find this page: please consider a line of products for those of us who want to build fully functional tech with a Lego pieces. (Please and thank you.)