Usually when we think of a music box it’s something that can fit in your hand.

Swedish musician Martin Molin, however, has spent over a year creating one larger than a person that makes whoever turns it into a one-man-band. Even more curious, the entire machine runs on approximately 2,000 steel marbles.

Dubbed the Wintergatan Marble Machine, the Wonka-esque device is programmed to play a 32-bar melody by dropping marbles — which are moved through a complex series of pulleys, tubes and funnels — onto its various instruments including vibraphone, bass, kick drum, and cymbal. As Wired point out, Molin originally only intended to spend two months crafting the machine, but that soon turned into 14 months.

Now you can finally see the incredible results and what’s just as exciting is Molin documented the entire building process on his Youtube channel. Watch the Wintergatan Marble Machine in action below and head to his page to see how Molin built it.