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Let's compare numbers and see why mine are different from yours

I'll probably regret asking but I tried to devise an absolute worst case scenario for phono preamp output maximum slew rate and still come up with a full order of magnitude less than what you say is unacceptable. Here are my numbers, where do we disagree?

A high output low cost mm cartridge could have an output in the vacinity of 5 mv for 3.54 cm/sec stylus velocity (high quality mm units have about half or less that output.) A worst case waveform for slewing could be a cymbal crash transient at maximum modulation velocity subsequent to complete silence. Cymbals reportedly have a great deal of sound energy in the 11 khz region. I'm going to assume the outrageously high output of 25 mv at 10 khz resulting from about a 17.5 cm/sec instantaneous stylus velocity. This is about 10 times the typical phono preamp sensitivity and I'd guess near or in excess of the overload point of many phono preamp stages. The period of 10 khz is 100us (microseconds) but the waveform reaches its first peak in 1/4 that time or 25us so the slew rate would be 25mv/25us = 1mv/1us = .001V/us. Assuming the phono preamp has a sensitivity in the range of 2 mv and a gain of 100 to match the high level input sensitivity of 200 mv for 1 volt output, the maximum slew rate at the phono preamp output would be 100 mv/us = 0.1V/us But you said 1V/us is not adequate and you would need to see 5V/us or better. Do you have an explanation? Data? Assumptions? Arithmetic errors?

In informal but careful listening tests looking for cartridge mistracking many years ago, the output of the Shure M91ED cartridge tracking at 1.5 g in an Empire 980 arm connected to Dynaco PAT4/Stereo 120 and to an AR amplifier driving KLH6 speakers playing the cymbal crash test on the Shure Audio Obstacle Course record sounded the same from band 1 through band 4 except for loudness. I got the same results with Shure V15 Type II improved tracking at 3/4 gram. Of course these were different preamps from PAS3X and you would probably consider all of this equipment "mid fi" by your standards. The point is that I didn't notice any difference in sound due to what you suggest are the slew rate limitations of the inexpensive M91ED cartridge, unless of course you would say that the V15 Type II is no better and also slew rate limited. I'd agree that many MC cartridges are capable of faster maximum slew rates typically due to about a 5 db peak in the 15 khz range resulting from an undamped mechanical resonance. This was typical for example of many Ortofon cartridges and possibly in a way audibly desirable during an era when many speaker systems had a significant high frequency rolloff and people were obsessed with keeping their tone controls at the detented 0 setting if they couldn't switch them out of the circuit altogether. Now of course they don't want to even see a tone control on a preamp.

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