Keyboard Synthesizer with Drums and GUI is a DIY digital synthesizer and drum set project designed for music enthusiasts, hackers and programmers. It uses an Arduino Nano 33 IoT (or compatible) as the synth processor and a Raspberry Pi Pico for drums and a graphical user interface on an OLED SPI display. The system features an ADSR envelope controller, 12‑key keypad, potentiometer controls, capacitive touch drum pads, DAC, op‑amp signal conditioning, LM386 power amplifier and speaker, allowing real‑time sound creation, looping and visualisation.