This is a short test showing the noise levels in hi gain sounds while using two ADC/DAC options:
1. 24bit integrated ADC+DAC codec chip WM8731
2. 32bit separate ADC AK5552 + DAC AK4452 with differential inputs and outputs.
Besides the obvious lower noise level the option 2 offers (dedicated hardware platform for the TGX4 Guitar Amp emulator project), the internal oscillation is gone. Integrated codec chips suffer from this issue due to internal construction, physical proximity between the input and output pins.
With separate ADC+DAC the layout can be designed to mitigate that problem.
github.com/hex...
forum.pjrc.com...