So how does the fiddle pickup sound run through an amp or mixer? Does it require EQ?

I agree on the interface. Get a good one and record it to a DAW that lets you use FX in the channels and busses. I'm partial to the Focusrite interfaces since they have very nice audio preamps built in to them. I run that into Sonar and use my FX as needed to EQ things.

Another option is to use headphones and a nice condenser mic on the fiddle. Certain types of mics can impart a warmer sound to the fiddle. I often use this now days to record my guitar... both electric and acoustic.

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