You are right refarding the ARO arm.It is a very warm/musical one without becoming lush.Judging from your listening tastes,i'd say a Sumiko blue point special cartridge would be the best bet and it costs less than $500.

One major factor to consider is the compliance of the cartridge versus the effective mass of the tonearm. In a perfect world this wouldn't be much of an issue, however we don't live in a perfect world. All records have some degree of warpage and this can effect how sell a cartidge tracks the non musical vertical displacement of the warpage. Cartridges with a high compliance are "weakly" sprung and can "bottom out" when used with a high mass tonearm. Cartridges with a low compliance are "stiffly" sprung and can be "launched" out of the groove when used with a low mass tonearm. Fortunately, cartridges and tonearms are somewhat normalized in values but there is enough variation that some tonearm/cartridge combination won't work well together. So your question is quite valid. I would suggest talking to your dealer and see what he recomends. They have first hand experience with these issues and should be able to keep you away from an incompatable combination. I would suggest that you make a final pick for a tonearm and then choose a cartridge best suited to the effective mass of that arm. Hopefully the literature packaged with your tonearm will guide you in whether to use a low, medium, or high, compliance cartridge.

As for the specific type, MM, MC, or MI, that's a matter of "flavor" and you'll probably want to audition some cartridges to see what suits you best. In plain english, buy whatever cartridge you think sounds best to you.

Art Dudley uses an Naim Aro on his Linn LP12. Because of a grounding design, he had some caveats about using the Aro on a Lingo'd Linn:

http://www.stereophile.com/artdudleylistening/205listening/index1.html

Peter,help us out a bit here.The Aro is an old arm.No one remember its specs.Is it loe,medium or high mass arm?

Peter.Scooter 123 answered that but if you are asking me, to be honest,i do not remember.It has been ages since i had to bother with such things.Easiest way to remember though, is you mate a high compliance cartridge with a low mass arm and a low compliance one with a high mass arm.I hope i remember this correctly lol

Peter,forgot to ask,did you purchase the Aro or you are just planning to ?

Also,i did some research and the Aro's mass is 11 gr which actually makes it a medium mass arm.In a few words,you can use just about any modern cartridge you wish.

Peter,i too am from the "musicality" camp.I hate sterile , over-analytical systems.Linn is a "warm" sounding table and so is the aro.Just don't overdo it or you'll end up with a "too much of a good thing" player.Pick a "fast" sounding cartridge (not neccesarily "cold") otherwise the "warmth" will turn into lushness and everything you play will become mushy and slow.

Peter, in an ideal world all records would be perfectly flat. If that were the case we would all want to have a very high mass tonearm. The reason is that the inertia of the tonearm would prevent the tonearm from trying to "wiggle" in time to the movement of the needle following the groove. Keep in mind that any response of the tonearm to the needle's movement will act to absorb some of the energy that should really be tranmitted to the "motor" in the cartridge. Which means that a high mass tonearm would, in theory, be more efficient and musical.

Unfortunately, it's not a perfect world and records aren't perfectly flat. Used with a highly compliant cartridge a high mass tonearm will cause the cartridge to "bottom out" at every warp (think of a softly sprung car going over a railroad crossing). So a high mass tonearm will require a low compliance cartridge. The problem is that if the cartridge is stiffly sprung (low compliance) the needle may be forced to "dig into" the record at every warp. Which means that a high mass tonearm may cause a bit more wear to the record as it is played. In addition a low compliance cartridge would be more effective at transferring the grooves energy into the tonearm. Fortunately, even those tonearms rated as high mass are light enough that record wear probably isn't really a big issue. However, I suspect that a high mass tonearm is more likely to cause wear than a low mass tonearm.

So now we have the low mass tonearms. I think that they are the best choice for most of us who live in the real world. The only problem is that, if mated to a low compliance cartridge, they are more likely to skip out of the goove on some musical passages and warps. In addition they will loose some low frequency response due to the transfer of energy to the tonearm instead of the motor assembly in the cartridge. So your choice of the ARO arm is probably a good choice.

One last thing that I should mention is that the mass of the cartridge can have a large effect on the total effective mass of the tonearm. Keep that in mind as your shopping because a heavy cartridge can probably turn a low mass tonearm into a high mass tonearm just by mounting it.

What I would suggest that you do is look at the literature for your arm and then talk to your dealer. If you make it clear that you'll return any incompatible cartridge I would expect that he'll be careful to recomend a cartridge that will work well with your tonearm.

Scooter makes good points.

Even beyond cartridge compliance, there is a cartridge characteristic I think I've noticed, but don't have an official Hi Fi word for...

...so please pardon me if I lapse into Hi Fi gibberish.

Like Scooter describes, the tonearm must do two things simultaneously. It must act as a steady platform for the cartridge (really, the tonearm is just an upside down cartridge platform) without imparting any extra non-musical signal nor subtracting any musical information. So, it has to act as a solid/neutral base of operations from which the cartridge can get its work done.

At the same time, since it is upside down, it has to "ride" the cartridge as the cartridge leads it across the record. So, in a bit of a paradox, the tomearm has to be both inert, yet reactive to what the cartridge is saying it would like to do.

There's other stuff the tonearm must do, but these two thing intrigue me.

Hence, we end up with all the tonearm and cartridge matching problems that Scooter described so well.

OK, so that's the preamble.

Some cartridges, beyond their compliance rating, seem alot "busier" than other cartridges. I haven