Tone arm resonance and cartridge compliance: How do they interact??

@lewm I think you misunderstood my reply. I was not insulting you and was not implying that you pasted from a text. I was saying that I was trying to avoid doing that myself. I apologize if my meaning was not clear.

I will restate my point: adding mass to a tonearm can be beneficial. But adding mass at the headshell (farthest point from the fulcrum) is problematic, will result in increased instability at the point of contact (stylus) and will not significantly alter resonance issues to the entirety of the tonearm. Mass is best added distributed along the arm but will have the most effect closest to the fulcrum.

br3098

Mass is best added distributed along the arm ...

Perhaps ...

... but will have the most effect closest to the fulcrum.

No, the opposite is the case. The further from the fulcrum, the greater the effect of the mass. The pickup arm works as a lever.

Dear @cleeds  : Maybe @br3098 is refering that near the fulcrum makesthe tonearm has more operationsl stability but agree with you about modified the effective mass.

R.

The pickup arm works as a lever

Exactly. And the further mass is added away from the fulcrum the more destabilizing the effect. Resonance (the original topic of this post) is increased. A pivoted tonearm is not just a lever, it's a mechanical amplifier.

I'm not saying that adding mass to the headshell does not have benefit. But there are also detrimental effects. From the perspective of decreasing resonance and other artifacts the best of all worlds is to increase total mass uniformly and proportionally across the entire length tonearm and headshell. Barring that, adding weight to the tonearm closest to the fulcrum will have the most damping effect and reduce resonance frequency change.

If curious, this paper on Tonearm Mechanics does a pretty good derivation of the resonance and the effects of mass.
http://www.cartchunk.org/audiotopics/ToneArmMechanics.pdf