#1
Out of these two, which one is better for acoustic guitar and micing amps?

From what I've read, the AT2020 is a nice mic with a little weakness on the low frequencies, but I've used a CO1U before and hated it because of it's exaggerated low frequencies.

I haven't read anything bad about the Snowball, and it has the 3 settings. Though it is an older, cheaper mic.
#3
Same. I don't know about the USB version, but I know the standard 2020 is a decent mic.
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