Advice needed: Output stage in Sony TA-E9000ES (CXA8042AS DAC)

[Groundloops]

Got my hands on a Sony TA-E9000ES AV preamp and looked at the output stage schematics. As expected I found lots of NJM4580 opamps in it, not really the ones to go with. I have no idea of output filters and stages for DACs, so I ask for some advice: Change opamps (AD712 for AD8620 and NJM4580 for LM4562 or OPA3134?) or just leave it as it is?

Here is one of the CXA8042AS DACs:



And here is the output stage (signal flow marked with red arraows):



Thanks!

[Groundloops]

Bump ...

[treuben]

It's ages old, this thread, but that isn't a dac - it's a digital volume control. I'm guess - just guess mind - that the AD712 was a set up as a digital filter and then njm the o/p amp. If so the 712 is a fast settling amp designed for the purpose. Replacing the o/p amp might do something though. 8)