What makes a good tonearm?

I'm entering the world of decent analog and believe I understand why the turntable design is critical (e.g., vibration isolation, balance and speed stability) but am scratching my head a little about tonearms. What makes a good tonearm good and a great tonearm great? The resulting sound is always the key, but what design characteristics contribute to that sound? Tonearms are a big investment and can be tough to change later so I'd like to understand more about them before I buy anything. Thanks in advance.

Showing 1 response by psychicanimal

If you take a close look at the Technics' 1200 tonearm you'll see the features of an outstanding tonearm. Full gimbal w/ extremely low friction bearings (published spec), s-shaped and bent at two unequal distances to avoid resonance, damped counterweight. It's a great design--a litlle heavy, being a cheaper version of the titanium EPA tonearm. THe tonearm is overall non resonant and neutral. Right, TWL?