Output shield for AK4490 Audio DAC

With our new USB only AK4490 based DAC, we wanted to give the DIY Audio world the possibility to build there own high resolution DAC. Of course it is very demanding to do combined analog and digital design. So we decided to make the DAC with an Mainboard and Shield that can be mounted on top of the DAC mainboard.   This output stage shield is configured for PCM filter and uses highly claimed OPA828.