Hello John,
Thank-you for your early reply.
I did consider the ADAU1451 and the AD1938 CODEC.
The ADAU1451 is a new part and the algorithm libraries are not completely available/ported yet. If AD updates the SigmaStudio libraries soon, the AD145x can make its way in. I am designing from scratch and the schematics will not freeze in another 10 days.
The AD1938 CODEC is nice. But is is costly. Moreover, it needs at least 8 low noise dual op-amps and the associated precision components for the ADC and DAC filters.
Spec-wise, the AD1938 will measure better. Sonically, will it sound better?