since the sp 404 has a mic input can i run my mic through the sp 404 before it goes to my interface (which would normally require a pre amp) ?

you're not gonna get a top quality sound just going through the mic jack-but- you can run your mic through a preamp,and run rca's from the preamp to the ins of the 404-and either sample your voice -or do what you're talking about and run it into your computer-the added warmth,etc-of your preamp will definitely make things sound better. Of course,all this kinda depends on the quality of your mic and pre amp. But the basic answer to your question-if you're not using a mic that requires phantom power-is yes....good luck,peace