best choice cartridge for my Lamm LP 2

To answer that question, I don't think its so much the impedence characteristics of the preamps, but rather how much gain (in db) either preamp delivers, which is a question of the preamp's design, number of gain stages, etc...

You might want to contact Lamm (Vladimir?) and ask them to recommend some possible carts.

It's very easy to match the phono input to the cartridge.

You really should choose a cartridge you like & can afford -- NOT one that seems to be happy with yr phono's standard input impedance settings.
Phonos are tools; accordingly, you match the screwdriver to the screw -- not the other way round... Cheers

I agree with Cmk, and I've always wondered what sort of cartridge the LP2 was designed for.

57db of gain is appropriate for cartridges of at least.5mv output, a bit higher would be better.

OTOH, 40 ohms input impedance is optimal for cartridges with coil resistances somewhere around 1.6 ohms. A coil resistances that low would typically imply extremely low output, like .1mv or less.

No cartridge I know of with a coil impedance below 2 ohms produces anything close to .5mv output. If there is such a cartridge it is very unusual, and LP2 users would be fairly locked into it.

Frankly, the LP2's gain and impedance specifications just don't belong together in the same phono circuit, and raising either one is not something many users could do.

Asking Vladimir is certainly a good idea, but friends of mine who've asked him did not get very useful answers. That eventually led them to different phono stages, ones designed for cartridges that actually exist. :-(

Dear Fjno4: I agree with Cmk. Now, your Ruby 3 is a very good cartridge, you are asking for a cartridge for your Lamm and that is an alternative but other alternative is not to change the Ruby 3 or think in other cartridge but better than that: change the Lamm.

Always the phonolinepreamp is critical and very important to obtain a high quality sound reproduction especially with low output MC cartridges like your Ruby3.

Regards and enjoy the music.
Raul.

I am open minded and want to look at any and all options I may have. That said, many great phono stages such as the ARC PH7, Herron,and others only have around 57 db of gain. Having already owned an Aesthetix Io Mk2, I cant think of an abundance of alternatives. I guess the Artemis with around 70 db may be something to consider, but beyond that I cant think of many tube based options.