Imagery counts for a lot with the minimalist band Morphine, who we can safely credit as the first band in rock and roll history consisting of a two-stringed slide bass, bari sax and drums. There, on the back of their latest album, are singer-songwriter Mark Sandman, saxist Dana Colley, and drummer Billy Conway, submerged in water and looking distorted but not unhappy. So it goes with this music, with Sandman singing gutsy art-R&B tunes with a voice like a gruffer, bad apple variation of Mark Knopfler. On the title cut, “Potion,” and an absurd ditty like “French Fries w/ Pepper,” the band projects its riff-based sound, without need for apology or explanation. Despite the peculiarity of the instrumentation, Morphine is no novelty act, but a new sound tapping into some fundamental resonance, some funk truths, lurking beneath rock legacy. In a real, hands-on way, it recognizes that, contrary to what rock lore would have us believe, real music power often comes from below.