Hi!

Thinking about getting a Shure sm58 mic. Anyone out there tried to plugg i direct in the sp-555?

Yes I've tried using SP555 live with microphone in SP-555. I tried to sing through it. It's tricky and very hard to get the volume level between Mic and the music that you play from SP555. When you level up the Mic volume to adjust with the music/pattern/sample it gives feedback because you really have to blow up the mic volume to hear your voice. If Roland made individual output for Mic and instruments it could have been fantastic. The volume issue remains the same when you use line-in along with samples but with Mic its even harder. Maybe others are not having any problem...

it works fine. just set your signal flow to "out" and turn off the track monitor in your daw.