Laser-cut basswood and wood glue. I took a laser cutter class today at NYC Resistor and decided to make whistles based on the classic design of organ pipes. If you have a laser cutter of your own, you can download the plans here.
The wood’s not polished or stained, just burned a nice brown around the edges by the laser. It smells terrible.
I made two sizes of whistle; they sound like this.