The Series III mixers use high quality converters from AKM. The AK5558 for ADC and AK4458 for DAC.
The new converters for the Series III mixer were chosen after considerable listening tests and comparisons. While sonically similar to the converters in the AI series mixers and Studio 192, the dynamic range spec is slightly lower. However, in our tests we found the difference to be negligible and on par with the competition.