Simply put, GuitarConnect Pro adds an instrument input to your iPad or iPhone. At one end, it gives you a 1/4" mono instrument jack that fits your instrument cable, and at the other end, a dock connector for your iOS device. Plug your instrument into the 1/4" jack and you have a noise-free, 100% digital connection from your instrument to GarageBand. And GuitarConnect Pro"s gain control lets you control the strength of your input signal.