best cartridge for less than $700 for AQ PT6 arm?

I nominate the Ortofon 2M Black. Should be a good effective mass/compliance match, and the reviews indicate that it provides a sophisticated, full-bodied, hi-res presentation well within your budget. Also cheaper to own than an equivalently priced MC.

It's what I'd get if I upgraded.

I agree with Viridian. The lower-end Dynavector cartridges have good speed and detail for the price. If you're looking for something warmer, the Grado Sonata can usually be found for around $325 as a barely used demo.

Hi All,
I have a question with regard to:
>>> I nominate the Ortofon 2M Black ...... Also cheaper to own than an equivalently priced MC <<<< and the comment
+++ I would look at the Dynavector 10X5 or 20X .... +++

Has anyone had a chance to compare these at all?
I am familiar with the sound of the 10x5 and 20X for that matter, and would think that the "2M Black" would be the better sounding cart, i.e. more resolved (by far?) than the 10x5 and less 'grainy?' than the 20X with an equivalent bass performance, something to say in terms of the 20X's bass power!
Can anyone comment on this at all?

BTW, this expectation is based on listening to a number of decent MM carts lately such as a P77, EEI 500, Empire S1000 ZE/X ... these are all real old-timers and sound better over all than the Dyna's mentioned --- not to say that those are bad carts in any way!
Now with the "2M Black" we see the latest interpretation of MM technolgy as well.

It's just that I lately found out, that some of these old MMs have more 'musical magic' than a lot of even more pricey MCs then e.g. 10x5 or 20X...
Greetings,
Axel

Thanks to all. I should mention that I use a Luxman C-1010 preamp which will play both MM & MC cartridges. I also use a Apt Holman preamp which can only do MM without a separate MC board. I have not had a chance to listen to any of the cartridges which are mentioned. It's difficult to find stores where you can actually audition different cartridges. I know of all the cartridges mentioned except the 2M Black. I have also heard the Sumiko Blue Point Special might be a good one to investigate. Any thoughts about that? BTW my speakers are Magnepan 3.3R's if that makes any difference and I am using 2 Carver M500T's as monoblocks.
Should I worry about the total weight of the cartridge and or the tracking force? I'm really looking for the best sounding cartridge, MM or MC if that means anything.
Any other hints will be especially helpful. Merci!