tracking ability definition


i am a little confused as to what the term "tracking ability" means when referring to a cartridge/stylus and how this translates to percieved sound? could anyone explain?

reason i ask is i recently received an response from KAB regarding my question about the difference between the Trackmaster II AE and the ortofon pros40, saying that the Trackmaster II AE has "fuller midrange and best tracking ability" while the Ortofon pros40 has "more transparent treble and punchier tighter bass"

would i be right in assuming that this means the stylus makes good contact with the groove therefore better reading the recorded sound and playing it more accurately, with more detail?
fadeawayman
Dear Fadeawayman : I think that the KAB people know-how about cartridge tracking ability is near cero, let explain me:

the Ortofon Pro S40 measure a tracking at 90um!!!!!. This measure is on the high value about cartridge tracking. Usually a MC cartridges stay between 70 and 90um and only a few on the 100um!!!!!.

So, the Pro S40 is the way to go. No question about.

Regards and enjoy the music.
Raul.
Raul, the trackmaster I am comparing it to has a tracking ability of 100um, even higher!

Thanks for your suggestions and advice.
Dear Fadeawayman : I think that with these two high tracking ability values you can't have any problem about tracking distortion with any standard LP but the Telarc 1812, at least I'm sure you can't heard it through your today system.

Regards and enjoy the music.
Raul.
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i decided on the pro S40 for my 1200. mainly because rock pop etc is most important to me. thanks again for the suggestions!