Sat for a couple hours experimenting with four different mic elements, and ended up using the Shure 65. Seems the old stand by, while not quite as hot as the other capsules, had a broader frequency range, Also had a little bit of grit to it - maybe because of its age. Got one in my Capiitaine as well, switching off between that and a wireless gooseneck mic, depending on the tune. Curious what other people opted for - what worked well, what to avoid, maybe saving others some time on their decisions.
The three row is a Hohner Compadre. Supposed to be violet, but the pinkest darn violet I've ever seen, in an Austin Powery sort of way. Tried a Panther, but seems a little clunky to me compared to the Compadre. Plays easy, don't have to bully the bellows. I've been running it through a Boss OC3 to get that bassoon octave. No, the sound isn't quite that of a lower reed bank, but it does beef it up for a fuller sound. Ain't no Baffetti, but at about a tenth or so of the cost, it'll work out fine - at least till I get in touch with that guy who keeps emailing me about sharing his bank account he can't touch and needs my help.


Steve

I started with Shure R-65s. They are the old reliable, standard issue, mainstay choice.

Of my 4 mic'ed accordions, I still have R-65's inside of two of them, and I have an external clip-on R-65 that I have available for use as well (when I want that clean, Cajun sound).

For my other two mic'ed accordions, I am using the capsule from Shure SM-57 mics. Like you say, they have a hotter signal. I am pretty happy with them all-in-all, but they do have a larger form factor that makes placement inside the bellows more tricky than other mics.

I don't have a big issue with unequal sound distribution. It's not perfect, but it is WAY better than what I started off with in the triple row, which was one of those cheapo crystal mics. UGHH - that was truly horrible.

One thing I noticed a couple months ago was interesting. I was playing the triple row through a new keyboard amp that I bought. It is a Behringer Ultratone. Being a keyboard amp, it covered the low end of the spectrum very well. I was playing something in the key of C, which brings in the lowest notes of the accordion. Note that this is a 4 reed, LMMM, setup. Lots of times when I am in C, I turn off the low reed, but for whatever reason I left it on that night (this was a Mardi Gras gig at a casino). I also had the amp cranked pretty loud. Well, when I got to some of those songs in C - WOW, the low end totally kicked butt. Seriously, I was looking around, like, "is that ME making all that sound?". Man, I was feeling the bass. It was pretty cool, and a nice departure from past experience depending totally on some lame monitors that I can barely hear for my personal sound.

-David