Since Astor Piazzolla revolutionized tango in the '60s with his "tango nuevo," it's been a challenge to find artists willing to help the music continue to move forward, rather than simply continue paying homage to its past. With the exception of the electronicists in the Gotan Project, most contemporary tango musicians seem content to hew closely to long-obeyed rules. Sandra Luna, thankfully, is not an archivist. On Tango Varòn, she gleefully upends long-held traditions of masculinity and percussive aggression to emerge with an album that's both self-assured and strong while being subtle and evocative. Luna's voice is resonant to the point of being threatening, but the husky romance of her delivery and the sparse instrumental approach of the album makes for an unlikely and wonderful combination of past and future.