How important is the tonearm?

paperw8, heres what I've seen with a Linn Sondek going from least to best tonearm available in the shop.

#1, quality of arm doesn't affect groove tracking, thats really a matter of good bearings and good match between arm mass and cartridge so that irregular record surfaces don't excite a wow/flutter effect. You can get excellent groove tracking in any properly made cartridge above $100

2# quality of arm does affect the ability to trace microtransients and not distort peak transients. A mediocre arm reduces that sense of "air" in a recording and direct to discs will make you want to shoot the arm and put it out of its misery. The arm basically rings like a bell at unpredictable frequencies and amplitudes in sympathy to the stylus vibration.

Better arms have fairly sophisticated schemes of minimizing resonances. Beware of any tonearm with dangling parts, thats a resonance PITA. An excellent tonearm should have a machined approach like jewel movement swiss watches.

01-30-11: Davide256
2# quality of arm does affect the ability to trace microtransients and not distort peak transients. A mediocre arm reduces that sense of "air" in a recording and direct to discs will make you want to shoot the arm and put it out of its misery. The arm basically rings like a bell at unpredictable frequencies and amplitudes in sympathy to the stylus vibration.

Better arms have fairly sophisticated schemes of minimizing resonances. Beware of any tonearm with dangling parts, thats a resonance PITA. An excellent tonearm should have a machined approach like jewel movement swiss watches.

i see. this sounds like a pretty reasonable explanation. i have a triplanar tonearm and one thing that i have noticed is that the tonearm seems very dead in the sense that if you tap the tonearm the material from which the tonearm is made deadens vibrations. an impulse tap contains a fairly wide range of frequncies so that test would suggest to me that the triplanar tonearm is not particularly prone to coupling longitudinal resonances along the wand.

Oh dear oh dear.
The old 'tap' test again..........

What's wrong with taps for a dead arm? Sorry, the devil made me do it.

Paperw8, most any tonearm is a complex system in itself. Sorry, no easy answers.

Tapping. Here we go again.