FreeDSP_INTEGRA

An integrated four-channel Class-D Anplifier embedded with a DSP processor.

Details are stated in the wiki page

Project Web page (Japanese)

DIY Audio Forum Thread

Variations

INTEGRA-QUAD BALANCED XLR INPUT VERSION

INTEGRA-QUAD RCA-PIN INPUT VERSION

Features:

        Double Differential High-Performance ADC Input Circuit
        Balanced-XLR Input  or Differential RCA-pin Analog Input
        Optical or Coaxial S/PDIF Input
        Amanero Combo384/YORK pico or XIAO RP2040 USB-Audio Input
        Raspberry-pi ZERO 2W Slot with control buttons
        TL-232R-3V3 USB-UART Cable Connection Pin-Header for Raspberry-pi
        AUX-ADC pin header
        Onboard two AUX-ADC Trimmer-POTs
        Optional Toggle Switch for DSP control
        External Front Panel Control PCB connectivity
        DC24V Single Power Supply

Block Diagram

Optional Board

Audio Performance

ADC Distortion Performance