For audio, we want to run the core with a lower volts per turn( and resultant flux density ). The more gently we run things , the better it works for audio( sweeping general statement warning!!!!! ).

Once we achieved the understanding that high-performance audio has a different set of rules than other things, the problem was solved. I got my main PS choke from them, 35 Hy( specified 30 min ) at reaasonable current and high voltage tolerance. It will work just fine for this linestage. Cost as much as the linestage's power Iron though....
regards,
Douglas