bt's ninth studio album, "a song across wires", was released worldwide on august 16, 2013. blending elements of trance, progressive house and electro, the club music-oriented album reached #5 on the "billboard" dance/electronic albums chart, and features four beatport no. 1 trance singles: "tomahawk" (with adam k), "must be the love" (with arty and nadia ali), "skylarking" and "surrounded" (with au5 and aqualung). on the album, bt also collaborates with senadee, andrew bayer, tania zygar, emma hewitt, jes, fractal, tydi and k-pop singer bada.