This Drum Pad is one of my fav ideas to make it myself. NXP's IMX RT Crossover MCU is powerful. I have the IMXRT1015 kit so started the project with that.
I used AFE shield board fromCypress. This is seated on top of the IMX RT over Arduino connector. The board has a PSoC4 analogue processor (MUC) in it.
The AFE shield has interfaces for OLED, CapSense, Switches and LED's and is accessed through i2C interface.
IMX RT side, using SAI to play the audio file at 16KHZ. I have created 12 samples (.wav file) and the raw data is stored in the music file. Based on the CapSense button press triggering the sound effect.
The speaker I used is from Boat, it has an internal battery so the only thing required is to feed the Aux input from IMXRT EVK.
I felt that the button sense over I2C is a bit slow and has a limitation when playing faster tempo music. Anyway, it's just a demonstration of my concept.
This drum has 3 modes of music set. The mode can be changed with the help of a mechanical switch (push button). Also, the volume can be controlled via Potentiometer.
The working video is here.