Futur3soundz XFM2

The Futur3soundz XFM2 is a 64-voice, 2-part, 6-operator FM synth with two built-in effects processors, and can be built for around $99. Based on pre-assembled development boards, the Digilent CMOD A7-35T (FPGA, USB, SRAM) and the Adafruit UDA1334A (DAC) and less than ten other components.