What's odd is that my last measurement (on a low-mass tonearm) also shows that dip. It is not really there (or at least not it is not as pronounced) in earlier ones, in particular the ones taken on my high-mass tonearm. Measurement FRs have been corrected to CA-TRS-1007.
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And, yes, you'd expect evidence pointing to a pronounced resonance at 20Hz. Goes to show that it is hard to translate Japanese compliance measurements and that people overreact to things without evidence. Then again maybe that dip above 10kHz is a related issue. The cap mod didn't make a real difference with the high-mass tonearm but I never tested it on this low-mass tonearm. I no longer have the cartridge so it would be great if someone else also measured in order to confirm if it is an issue.
Here it is on a high-mass tonearm. Ignore that FR explosion above 15kHz, that is the test record, and ignore the high-pass filter on the preamp.
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I can see why these are popular given the convenience MC cartridges affords on loading. Consistent results given proper set-up. (That and Stereophile/Art Dudley wankery. Don't @ me, I didn't write, "dependably musical, unfussy sound.") But distortion above 10kHz is high (a lot of Denons have this issue), output is extremely low, and the stylus doesn't last long given the shape. Personally I don't think it is worth retail price today, which has gotten waaaaay too high.
Perhaps Stereophile should have reviewed a Radio Shack cartridge like this one:
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