The Magnetic Fields are hardly suited to conventional rock performance. Due to a hearing condition called hyperacusis that amplifies sounds to the point of screeching feedback which plagues lead songwriter Stephin Merritt, The Magnetic Fields can’t have any percussion onstage. Merritt cringed and plugged his ear at every audience applause and although they have an album called Distortion, they certainly can’t use any of it when playing the tunes from that 2008 album. In…