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There is a technological advantage to the LOMC

Posted by EdAInWestOC on December 29, 2016 at 07:03:13:
The high inductance/impedance MM/MI cartridge forms a low pass filter when interfaced with a phono preamp. On most MM/MI cartridges the low pass filter has an effective frequency of approximately 20kHz.
The problem is that a low pass filter doesn't just operate on the frequencies above its effective frequency. At frequencies as low as 1/10 the effective frequency (2kHz for this example), the low pass filter introduces phase shift. This can impart the same sort of issues that tone controls do to the music.
Tone controls have been removed from most audiophile products due to the phase shift introduced to frequencies across the audio band. In other products tone controls are included but they also include a bypass switch to remove the tone controls from the signal path.
All of this works around the problems that a low pass filter can introduce. The same problem exists in the low pass filter that the MM/MI cartridge plus phono preamp interface creates. It cannot be eliminated unless you reduce the impedance and inductance of the MM/MI cartridge.
There are several manufacturers that have offered low output versions of their non-MC cartridges. SoundSmith, Grado, Stanton and Pickering come to mind as manufacturers of cartridges that worked around this issue with low output, low impedance, low inductance models.
The transparent open sound that a LOMC cartridge possesses is likely due to the lack of low pass filter issues in its interface with the phono preamp. Its not a free ride and the low output MC requires a stepup transformer or pre-preamp stage to boost the signal level.
This extra stage of amplification introduces another place for something to go wrong. That plus the fixed stylus assembly makes LOMC cartridges unacceptable to some people.
In practice a high quality, high output MM/MI cartridge can get very close to a LOMC cartridge. In the end, a high output cartridge drags around the low pass filter issue with it and that cannot be removed from the reproduction. Many people find a high output cartridge perfectly acceptable.
I did until I heard a LOMC through a top quality front end. That ended the argument for me. For others its not an issue. Maybe you need to try a LOMC so you can make up your own mind.
Ed