““Mono” takes a patient ear. It begins in the most minimal manner. Just one introductory beat and an oozing hum of bass that stretches mysteriously. A vocalist–Rahm Silvergrade–enters, hush-singing in a manner that might initially leave you making comparisons to Oliver Sims of the xx. Stick with it, because “Mono,” the latest single from the New York band Altopalo, is certainly worth the investment”