Rothwellaudio wrote:.....Anyway, it makes the effects of loading mc cartridges even more mysterious. From an electrical point of view the difference between a 100 ohm load and a 500 ohm load to a 10 ohm cartridge must be miniscule, yet there are people who swear that they can hear a difference. I wonder how much of it is imagined.
If any audible effect of varying loading R is real, it doesn't have a mechanical cause. More likely a magnetic low power non-ideal, IMO.
For completeness and interest, the only MM for which I have published mechanical impedance data is Shure V15 II, 0.048Ns/m@1kHz. Mechanical power 5cm/s@1kHz is c 115uW (versus 375uW for DL103, V15II is lower mech impedance, of course). For MMs, electrical load power is even smaller, c 0.3nW into 47K. So MMs have even less electrical load variation effect on mechanics than MCs. But both MM and MC have effectively zero mechanical influence through electrical load variation.
I don't recall posting these results before, but it is possible I did.
I think any real audible effect in MCs of loading variation is most likely to have an origin in magnetic non-ideals, and their variation with level.
Lastly, I've seen that Shure peak velocity data before, and recall that it doesn't stand scrutiny. IIRC, it was mooted it may include noise pops. I suppose one would argue that is still relevent to headroom. But it doesn't change anything here. And usual caveats about Shure marketing material from that era must apply !