From what I've seen, you need a mixboard [or whatever the hell those things are called]. It has several jacks for guitars and microphones. You plug each jack into the board, and the board gets plugged into the computer. A mixboard [as I have dubbed them] has dials for each channel, so that you can adjust volume, master volume, bass, etc. Fair warning, last time I checked they were quite expensive. If you go into a place like radio shack and explain it to them, they'll know what you're talking about. And RadioShack most assuredly has them. Hope this helps.