What I found is that the channel strips in MainStage work in audio instrument , or software instrument or in Midi that you can use from the selection already made or make patches using available plugins , and set them as a channel strip . . I left Midi out as I am using a real instrument ( electric / acoustic guitar ) . I found out that it seems so far .. LOL !! That only the audio instrument channel strip will work with certain real instruments . The guitar being one of them . There is a small mono / stereo icon under the volume switch in the audio instrument channel strip . I pressed it and voila I got my sound to work . This is not present in the software instrument or Midi strips . I am somewhat disappointed because I can only use Logic's dynamic effects such as Sculpture , or ESX 24 when setting a channel strip up as a software instrument track , and this does not allow my guitar to be used . Is Sculpture not a guitar software ? It seems that it is , and a real shame that I can only use it with samples looped in the browser that are part of Logic's software music ( Jam Packs etc ) , or with Drums etc ?