Did you have to use such an annoying font?
Anyway, whats best depends on the appliction and the mics and the soundcard.
If your soundcard is a soundblaster card whats best is to get a better soundcard. If thats all you can afford then a mixer would be better than the onboard preamp. Make sure it runs into the line in, never bother with the mix input, it sucks.
But if you already have a good sound card like an M-Audio Delta 44 then its best to use it with an external preamp. A mixer has preamps built into it and thus the mixer can be used for a preamp.
The best setup is to go directly from a good preamp into the input on the soundcard. Unless the soundcard has a highend preamp on board like the M-audio delta 1010LT and Aardvark direct pro cards
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