The pop duo Karmin recently dropped by Gibson’s studios during a stop on their tour in support of their acclaimed new album, Pulses. The band—which centers on singer-rapper Amy Heidemann and multi-instrumentalist Nick Noonan—applied their self-described “swag pop” to a mashup of Pulse’s title track and Pharrell Williams’ “Happy.”

Heidemann employed a Min-Etune™ system to tune the guitar and for something else you might not guess. Check it out!