As Psychic Twin, Erin Fein’s songs are so illusory it’s sometimes hard to remember there’s only one person behind them. “In an ideal situation,” she says, “there would have been two of me singing and playing the music.” Her doubled-over vocals and counter-melodies ripple over a simple, pulsing beat, occasionally touched with tambourine or glockenspiel. In an ongoing series of 7"s, starting with her self-titled debut in 2011, Fein has been writing deeply personal lyrics about isolation and the darker side of love. “Unlock Yr Heart” is the first material Psychic Twin has released since the Strangers 7”in March, shortly after Fein relocated to New York. It proceeds not unlike Grimes’ “Genesis”, with the same thick-bodied bass anchoring both singers’ haunting, feathery inflections. Fein’s shimmering voice swoops in and out of itself, mirage-like, until she peeks out of the vocal effects during the chorus to suddenly shout, “Make you stay!” as if we had forgotten she was there.