The sound of a shamisen is unusually sharp and exact, even in the world of plucked string instruments. Each hit stands out, as isolate as the twang of a banjo. Portable as guitars, they’re popular with Japanese folk musicians. On Artificial Lover’s Nava, Oouchi Kazunori gives his shamisen a vortex presence, large and central, distorting the sound electronically, fraying it, cutting into it, or putting it at the bottom of a canyon of other noises, adding clicks and crunches, bird caws, turning this small instrument into the core of a massive filling of space, with vocal drone loops, industrial pounding, spasms, twitching,  then swings off into a fragment of Bizet’s Carmen. And I don’t think it’s unusual among Japanese underground musicians, these moments of jokey-seeming calm, torn apart by train wrecks. The neat shamisen is invaded by its opposite, a splattering orgasm, but the invasion is not totally serious,  asCarmen floats through, the violence is invaded by whimsy.