Cartridge break in

Varies with the cartridge/compliance material. Don't be surprised if you have to readjust the VTA, along the way.

Thanks.
Just switched from a SoundSmith Zephyr to a Lyra Kleos.
The Kleos has more of audiophile everything: bass, imaging, impact…
But the high end is too edgy for my system and vocals have a papery quality. I'm hoping that this will tame after some hours of break in.
Otherwise back to the Zephyr.
Rest of the system: VPI Aries 3, VPI 3D 10" tonearm, Musical Surroundings Super Nova phono stage, ARC preamp, Bel Canto Ref500 mono amps, Joseph Audio Pulsar speakers.

It varies. Suspensions for different cartridges are made from different materials, some soft, some hard. Different materials don't all wear at the same rate, do they? And, yes, the VTA may change during the process.

Maxh nice system you have. Good luck with the kleos. I have never had any component or cable change that much over time. If I don't like it out of the box I usually don't change, but that's me. I know others have very different experiences. Hope it works out.

Agree with Rodman and Mosin. With regard to Pops' experience, I've experienced both. Some cartridges change wildly in the first 25-100 hours, including basic changes in character - particularly at the frequency extremes. Others barely change at all.

Some suggestions:

Make sure you're cleaning the stylus effectively (ie, Magic Eraser + brushing) after every side

Make sure your LPs are truly clean

Check with VPI to see if they recommend additional headshell weight for the Kleos (they can provide)

Try increasing VTF in .01-.03g increments, listen for some taming of high frequencies

Try lowering arm height by TINY amounts, listen for closer integration of HF harmonics with their lower frequency fundamental

Try changing the phono input impedance, which is adjustable on your Musical Surroundings.