I find that capacitors affect sibilance quite a lot. The better the cap, the less sibilance (in general). There is a cap thread concurrently.
Also, the stability of the phono stage can contribute IIRC.
Other aspects of setup you have already addressed - but you may find that setting VTA so that the tail of the cartridge is down improves things.
Good luck.
Also, the stability of the phono stage can contribute IIRC.
Other aspects of setup you have already addressed - but you may find that setting VTA so that the tail of the cartridge is down improves things.
Good luck.