eeNews Project Focus: Super Flexible Audio DSP FX Processor

Introducing the Audio DSP FX Processor board, a cutting-edge device that combines an ESP32 microcontroller with high-quality audio inputs and outputs. While it may seem like just another development board at first glance, this innovative product offers much more than meets the eye. What sets the Audio DSP FX Processor apart is its integrated audio codec with a built-in DSP capable of processing audio independently, making it a powerful and versatile tool for audio enthusiasts.

The functional block diagram of the Audio DSP FX Processor reveals its intricate design, with the ESP32 and ADAU1701 processors connected via various buses. At the core of the diagram lies the I²S bus, responsible for transmitting audio signals between the two processors. When the DSP handles all audio processing tasks, this bus remains inactive, showcasing the board's efficient use of resources.

Furthermore, the I²C bus enables external control of the DSP, allowing devices like the ESP32 or Arduino UNO to interact with the processor through the extension port. While the DSP can also utilize SPI for communication, the decision to implement I²C highlights the board's focus on compatibility and ease of use.

Another key feature of the Audio DSP FX Processor is its EEPROM compatibility, facilitated by a dedicated bus for reading from and writing to the EEPROM. For instance, in Selfboot mode, the ADAU1701 relies on the EEPROM to store its program, which can be loaded wirelessly or via USB by the ESP32. This seamless integration of components enhances the board's functionality and convenience.

Moreover, the board boasts an audio I/O bus with two input channels and four output channels, each equipped with specialized filters for signal processing. While the inputs undergo filtering within the DSP, the outputs benefit from passive or active filtering mechanisms, ensuring optimal audio quality and clarity.

With additional features such as a USB-to-serial converter, optically isolated MIDI input and output, and support for up to four potentiometers, the ESP32 component of the Audio DSP FX Processor offers a comprehensive set of tools for audio manipulation and control. Furthermore, the inclusion of Wi-Fi and Bluetooth capabilities through a built-in radio module enhances the board's connectivity and versatility, making it a valuable asset for audio professionals and hobbyists alike.