@Ron Resnick FWIW Grado's website lists the Grado Epoch3's Compliance: 20μm/mN.
I'm not sure why Grado would list this compliance number if it was in actuality 10μm/mN. Grado doesn't say whether their reported compliance is at 10Hz or 100Hz. If at 100Hz then the number would need to be increased (by a factor of 1.5X according to some) not decreased. Why wouldn't we rely on what Grado reported the Epoch3's compliance to be?
I'm not advocating that
@mtemur isn't correct in his assessment of the Grado Epoch3 compliance number. I just don't know how he got there and I don't understand how or why Grado would report it incorrectly.
What this thread (so far) seems to demonstrate is that the declared compliance numbers may not be reliable and the published tonearm effective mass numbers may not be reliable. Damping also may play a factor and apparently isn't taken into account by the calculators. If the inputs aren't reliable, then why is using a "calculator" a good idea?