Gillian Welch’s “Revelator,” the sort-of title track to her celebrated 2001 album Time (The Revelator), was a sorrowful narrative ballad voiced in Welch’s forlorn alto, surrounded by bare acoustic guitar. The version by electropop duo Papertwin retains all of the original’s sadness, but replaces the guitar with bright, blinking synths and emphasizes the harmonies in the song’s chorus. The result feels like it transports the song from the desert to the tundra, and the heartache at its core becomes chilly and remote. It suits the song well — the two versions exist on opposite ends of the spectrum of sorrow (Welch seeks comfort; Papertwin seek isolation). But both renditions have their own unique rewards.