Changing guitar amps can affect sound as much as changing the guitar itself. The Kemper Profiling Amp can learn and mimic the sound of any amp. Musicians connect the Kemper to the input jack on the amplifier they want to imitate; the Kemper then issues a series of test tones (squeals, hisses, buzzes), while an onboard microphone records the feedback. With that data, the amp runs custom algorithms that convert the feedback into a savable setting. The amp can store up to 1,000 of them. $1,900