Waiting on some flooring to ship out of Dalton GA for the house, so back on the bench after a long break.
All four TDK MA-C90 tapes I recently picked up complete processing on the Microscan system with no errors.
So, TDK D, SA, and MA test tapes now very reliably process, every single time.
The Sony Duad Fe-Cr immediately fails to auto bias, it may well be bad as well as the earlier MA tape I was using.
Later I'll try manually biasing them, and see.
The four TDK MA have some nice jazz on them that I've been enjoying with headphones, sounds very good, but the test equipment shows there's room for high frequency improvement in the playback EQ.
So, the playback EQ.
These NOS Sendust heads I'm using were made for earlier machines than the late production CT-A1 which used Sendust Ribbon heads.
Going to try that Tascam head and see what it gets me.
Decided I'll anchor that sandwich head in the square barrel with clear finger nail polish.