Musician Matt Kessel quite masterfully performed harmonic covers of both “Amazing Grace” and “The Star-Spangled Banner” at the same time on the same guitar. His right hand was playing the melody of the first song, while his left hand was playing the bass line of the second.
Can you hear both songs being played? This is my arrangement of “Amazing Grace” and Star-Spangled Banner” to be played on one guitar at the same time. The high notes (harmonics), are Amazing Grace, and the low notes are Star-Spangled Banner.