MC sounds fake. MC has false over exaggerated detail. MC has a weak
presence region. MC has s weak midrange. MC has weak bass and midbass.
MC sounds terrible with step up transformers. MC is noisy with a lot of
mid fi phono preamps. MC sounds anemic with anything less than 60dB of
gain. MC doesn't work well with tube equipment.
All of the above statements are false.
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With regards to the original post, Its been my experience that the ability of the arm to track the cartridge properly is far more important than what cartridge you have!
Loading of cartridges is a poorly understood issue in the audiophile community. The loading issues for a MM are quite different from that of LOMC; the latter don't need any loading at all (the stock 47K input impedance of nearly all phono sections is fine) but MM cartridges are different because they have much higher inductance (which is why they also have more output). The higher inductance means that the loading directly affects them at audio frequencies whereas LOMC cartridge loading generally affects them at Radio Frequencies. As a result, to get the best out of MM its a good idea to load them correctly.
This loading has an effect on the cartridge as you are asking it to do more work. This means that the cantilever will be stiffer than the designer may have expected and so this can affect tracking.
If there is any advantage to LOMC cartridges, it is this latter point, as they need no loading at all.
(You may read quite a lot about loading LOMC cartridges, and if you do, here's the issue in a nutshell: the loading is there for the benefit of the phono section, which is unstable *if* the loading is a requirement. Other, stable, phono sections with the same cartridge won't need the loading to sound right.)