New Kiseki blackheart cartridge not sounding right.

Double check the alignment, overhang, VTA, VTF, azimuth, etc.  Can you adjust the load of the preamp at all?  More burn in time is likely needed too.

S’s are to much and sound smeared.

On all records? 

upper frequencies are too pronounced.

Change the loading

Try all the excessive sibilance troubleshooting recommendations. If that fails, time to have it looked at by a shop, or someone who makes house calls.

I have a Blue and have been curious about the Blackheart That's a $4K cart-it better sound like one!