Back in the old days, it took external guitar effects pedals to modify a guitar’s sound. As computer processing power has been growing at an exponential rate, software-based effects modelers have been becoming more common. [Matthew]’s dad is running Guitar Rig 5 modeling software on his Lenovo tablet. Although it works well, it is a hassle to change effects and amp models while playing. That’s where [Matthew] comes in. He’s built a foot pedal controller so his old man can change up those sweet sounds on the fly.
Guitar Rig 5 has the ability to change presets with key presses. Even so, it would still be a hassle tapping a keyboard while playing, whether it be physical or on-screen. Since an Arduino-compatible board with an ATMEGA32U4 chip can be used to simulate an HID device, [Matthew] decided to use one as the basis for his project. Standard push buttons mounted in a project box indicate to the microcontroller which keyboard commands to send to the tablet. There are 4 buttons for 4 presets on this build but any number can be used. When a button is pushed, the associated keyboard command is sent to the tablet via a USB cable and Guitar Rig 5 responds to that command by changing the preset. And just so you know where you are, an indicator light adjacent to each button shows which preset is current.