
OK, given what you mention, I think that this turns into a broader discussion.
If you were thinking of the Tascam model 12, and you aren't an experienced microphone user, here's what I'd propose you do:
Get a Behringer mic first. They're cheap, but they work (they're basically modern clones of classic, widely-used microphones), and they will give you an opportunity to practice your skills. Remember that dynamic microphones produce low signal levels, compared to line-in synths, but don't need phantom power. Diaphragm mics generally want phantom power (but may have their own power supplies or batteries, depending) which would mean that you'd turn on the phantom power when plugging them into your Force.
The Force is a perfectly acceptable place to plug in your mic, by the way. Yes, mixers give more options but don't forget that the Force includes a perfectly competent virtual mixer.
Now, on to the Tascam 12 topic.
If you want it as a mixer, that is cool, but the golden rule of mixers is to get more channels than you think you'll need because running out of channels sucks.
If you want it as a recorder, that is perfectly good too but you may find that it makes more sense to look at Tascam's portastudios for the purpose because they offer real mixing options as well as simply slamming in a number of channels. It's kind of old school in some ways, but it's more powerful than you might think. The Model 12's big brothers also bring joy to a party, but don't do the same complex multitrack recorder things that the portastudios do. (And I mean it about the power of the portastudio line. I can grab mine, a bag full of cables, and go to record a band and then, while the band has a couple of beers, produce a rough mix for them. Once you learn the ropes, it's a surprisingly useful way of laying down tracks.)
Alternatively, if you want to get active on the computer (although you make no mention of this) you may be better off with a decent USB audio interface, with a reasonable number of channels in and then use your computer as your recorder, mixing and mastering tool.
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