Sumiko Blackbird with Linn Kolektor - good match?

I'm using the Sumiko Blackbird on a Rega P25 through a Linn Kolektor preamp. My digital front end is outperforming the analog front end which is a first for me! I previously had a Super Elys cartridge which outperformed the digital stuff. Any thoughts on how to improve? Someone recommended changing the phono stage to a Pro-jectTube Box SE ll. Or could it be a cartridge mis-match? The Linn Kolektor is rated 2.5 MV input which matches the Blackbird so I don't believe that is the problem.
I use the same cartridge/turntable combination. I use a WhestTwo phono preamp with a Kairn (and now an Exotik). The Blackbird gives fabulous sound in my combo, so the phono preamp is probably the thing to focus on, as the other person suggested.