I have to do a show in a few days and I have a MIDI keyboard in Mainstage. I need to output to speakers. Would it be possible to get a 3.5mm to 1/4" converter jack and plug a guitar amp into the 1/4" side so I could use the amp as the speaker. Would this blow the soundcard? I've been searching around but most things I have read just talks about plugging in a guitar and not an amp.