Voodoo Lab Amp Selector allows you to play up to four different amps at once. Create tone layers or switch between multiple amps in any combination.  The programmable switching is completely silent with no clicks or pops, according to the company. It can be configured to switch each output independently, layering up to four amps, or function as an A/B/C/D switch. Other features include a buffered tuner or split output for slaving additional devices, and a second input that can be used to switch two instruments into different pairs of amplifiers or for stereo operation.