I built a set of Lego headphones and vacuum tube amplifier as a qualifier entry into our LUG's annual Luminary Brick Builder competition - a very similar tournament as Iron Builder. Our seed part for the qualifier was "any rubber Lego tyre". The amp is loosely based on xDuoo TA-26 Tube Headphone Amplifier, the headphones are my own design. Only loosely interesting on this forum I guess.
