A:Answer Theoretically, yes you could. If your guitar has passive pickups, then you could plug it into the mic input while that input is on very low volume and gradually turn it up to the desired volume. Note that it is not built for Instrument inputs, and the sound may not be what you are expecting. If you have an active pick up, such as an acoustic guitar with a piezo pickup, most of those will output a line level signal and in that case you can plug it into the Aux input. Note that plugging an active or line level pick up into the mic input can damage the speaker.
