Can someone explain "Moving Iron" vs."Moving Coil"


I recently got back into Vinyl, and I bought a Sota Sapphire, with an Alphason arm and a Grado cartridge. I asked the previous owner if it was a moving magnet or moving coil cartridge - he told me it was a moving iron. I've got a Classe DR6 preamp - do I select MM or MC on the back of the pre ? I started off with MM and I don't seem to getting sufficient gain, I don't want to switch to MC, as I'm afraid the output of the Grado might be way too high for the MC phono stage. Am I being paranoid, or should I just go ahead and flip the switch to MC and ride the results? Thanks.
dbamac
The Grado wood body cartridges are available in both high and low outputs (4.5 & .5 I think). Grado's phono pre which I assume was designed to match these cartridges has a choice of either 45 or 62db of gain. Your cartridge could be a low output model. Try both settings on your preamp and go with the one that sounds best.
Good info Bld. I didn't know that they offered two different output levels for their cartridges. 4.5 mv would be plenty for most any MM phono stage. The .5 versions could be used with MC inputs, but one might want to check the loading. Some MC stages use different loading characteristics than their MM counterparts.

For some reason, i was thinking that Grado's weren't as low as .5 but not as high as 4.5 mv output. Dropping somewhere in the middle there would put someone in a bind in terms of having "almost" enough gain on the MM stage while having too much output for an MC stage. Sean
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Should have done some research before my previous post. The current models have outputs of 5mv & .5mv, the gain on the phono amp is 40 or 56 db.