They are at Shinagava Musen Co. LTD simply call it: "The finest cartridge in F9 series!"FWIW, that isn't how I read it. It says, in part:
The F-9F ... is the finest cartridge in the F9 series suitable for reproduction of compatible discrete 4-channel records as well as 2-channel and matrix 4-channel records....While as you indicated the F-9F has the widest bandwidth (which is presumably advantageous when it comes to reproducing some of the quadraphonic formats), I would interpret the combination of the two statements above as being ambiguous with respect to which cartridge is better **for the reproduction of stereo records.**
The F-9E has, in addition to the excellent features of the F-9F, the ability to provide the finest reproduction of stereo records.
Regards,
-- Al