BLONDE REDHEAD - Melody Of Certain Damaged Lemons LPNew York City's Blonde Redhead developed a reputation as Sonic Youth imitators, because their sound originally depended on the same discordant guitar points and sexless machinelike rhythms. But over the course of five albums, they've grown out of that heady shadow. Incorporating sinister keyboards, conventional melodic guitar lines, and a stronger grasp of songwriting ("Melody of Certain Three," among others, is hummable), Blonde Redhead is emerging