What makes a good tonearm?

Speaking in generalities, a non-suspended table will tend to sound "punchier" than a suspended one. For much the same reasons, a gimballed arm will tend to sound punchier than a unipivot. A more stable base for the record and cartridge will allow maximum energy transfer from groove modulation to cantilever, with less loss of energy to suspsion or arm movement. If transient speed and dynamics are your goal, keep those aspects in mind.

Thanks all for the great responses. You inspired me to research the heck out of this. I'm very excited to report that I completed my order for an Origin Live Sovereign turntable with the Origin Live Conquerer tonearm and the Dynavector XV-1s cartridge.

The Origin Live units have been getting great reviews (e.g., the latest Bound for Sound) and I was able to get a very fair price on this combo which is just slightly used. I'll be plugging that into my PBN Olympia fully balanced phono preamp (FET, separate battery power supply). I should be getting the whole rig in a couple of weeks and will report my findings.

Thanks again. I ended up spending more than I thought I would, but the price was right and this'll save me an upgrade later ... famous last words ;-)

Dear friend: You can't say " I want to buy a tonearm ". When you want to buy a tonearm, you always have to think about it " wife's ": the phono cartridge. You can't separate, tonearm/cartridge is a "combo buy ". Go with you audio dealer and talk about this issue.
Regards.
Raul.

If you're low on cash and have moderately skilled hands, buy a used (meaning cheap and old) Rega Planar 3, and rebuild it; plus, do all the tweeks, thereby turning it to the equivalent of the "Sota Saphire". You also get the tone arm with the TT, which can be upgraded with new wire.

All the instructions for doing this are on this forum.

Check out the Audiomods arm. Made in the UK by a master machinist, who uses only the Rega 303 arm tube, all other parts made by himself. A very interesting set of design choices.