MM or MI Cartridge?

Wolfie, Good point about the relationship between hysteresis and core material, or lack of same. But to my observation, the three types do group well apart from each other if you base it on inductance. LOMCs are always much less than 100uH (micro-Henries). Many are actually down in the 10uH and below range. Whereas MI types typically measure in the low mH range, and a classic MM will measure 400mH and higher. The difference between 10uH (for a LOMC with low internal R) and 500mH (for a classic MM) is 50,000X! But I still stand by my reasoning (see above) and my listening experience that leads me to believe the difference in inductance does not make LOMCs inherently superior to MI and MM types.  So, you and I agree on the end point.

Forgot also to mention typical compliance numbers that might affect response time. MCs typically exhibit lowest compliance. The exceptional MCs that exhibit higher than average compliance are the ones I like best.

Moving coil cartridges do indeed have the lowest inductance of any of the three types, by far, but they also have the highest moving mass. Moving iron type cartridges have the lowest moving mass on average. MM types are somewhere in between. Therefore, any response retarding effect due to hysteresis caused by inductance is compensated for by very low moving mass in the case of the moving iron cartridge. Which may explain why the general conclusion that MC cartridges exhibit superior high end clarity, based on hysteresis alone, does not conform to my long-term observations of the performance of the three types of cartridge.

Jason, kudos to your friend with the Marantz-Futterman-Quad system. That’s a vintage combination to rival many modern high end systems except it needs a subwoofer. Back in the early 70s, I owned a similar system save for using KLH9s, first one pair and eventually two pairs, in lieu of the Quads.