Controversy, or intent to promote revolutionary politics as expressed through their music both blatantly and covertly, characterizes the main artistic drive behind two important acts touring through Greece this week. The seasoned hip-hop activists Public Enemy rewrote the rules of rap in the late 1980s, both musically and politically, as its authoritative leader Chuck D helped steer hip-hop toward a heavily politicized pro-black direction. The group will play two shows in Athens this Friday and Saturday at Ark No. 6 (18 Themidos, Tavros, tel 210.338.8400) and a third date in Thessaloniki at the open-air Lazariston Monastery venue. And the relatively more recent Godspeed You! Black Emperor, a somewhat reclusive Canadian instrumental collective that has operated in more mysterious ways to convey an anti-establishment message, is returning to Greece a little over a year after its first visit here for sold-out performances. The Montreal-based act, which has just released its fourth album, «Yangui Uxo,» will be playing two shows in Athens, tonight and tomorrow, at Gagarin 205 club (205 Liosion, tel 210.854.7600). Though the two acts stand miles apart in musical terms, their underlying ideological similarities are too many, and too fanatically implemented, to ignore. An obvious meeting point is the common rebellion of both acts against the music industry. Public Enemy, in their fiery history’s latest controversial chapter, have deliberately been without a record deal in more recent times. The influential hip-hop act’s decision to become one of the first major acts to offer its work to fans through cyberspace, following the release of several strongly influential albums advocating pro-black consciousness on the hip-hop powerhouse label Def Jam, carried heavy implications for the industry. As for the visiting Canadians, Godspeed – its abbreviated name – the act has put out four albums on its own tiny label, Constellation, despite considerable interest from several far larger labels. The Canadian act, nowadays a nine-piece unit comprising mostly guitars and strings backed by two drummers following a fluctuating line early on in the mid-1990s, emerged from Montreal’s squats. It began by playing to friends and providing soundtracks for obscure films. Together, they play troubling, expansive material that strikes dynamic extremes. The music, all instrumental, typically opens softly before a developing crescendo creeps in to propel the material into a heightened frenzy that tends to get roaringly loud at live performances. Despite the act’s disregard for the music industry and hostility against the entertainment industry as a whole, Godspeed recently agreed to provide material for a new film by Danny Boyle, the director of «Shallow Grave» and «Trainspotting.» According to Boyle, the Canadian act, reached over the Internet, needed to be pressed and persuaded before it was finally convinced to offer some of its existing material for the score of the director’s latest film, «28 Days Later.» Returning to Public Enemy, the hip-hop act led by Chuck D was formed in 1982 when its frontman, who was studying graphic design at the time, bonded with two fellow students, Hank Shocklee and Bill Stephney, also co-founding members, over hip-hop and politics. After initial reluctance, they eventually signed to Def Jam, the label co-founded by one of America’s music visionaries, the producer Rick Rubin, whose more recent feats, incidentally, include revitalizing the career of aging country legend Johnny Cash on a more recent label launch, American Recordings. With their second album, 1988’s «It Takes a Nation of Millions to Hold Us Back,» which blended avant-garde sounds with old-school funk as a vehicle for Chuck D’s aspirations for a revolutionary hip-hop group, Public Enemy attracted an immense crossover following to suddenly make hip-hop a force for social change. After a hiatus in the mid-1990s, following Chuck D’s decision to sever ties with Def Jam, the frontman founded his own record label and publishing company before the act returned with line-up changes. He released a solo album in 1996, «The Autobiography of Mistachuck,» and, a year later, also published an autobiography before teaming up with his act’s original team of collaborators, known as the Bomb Squad. By 1998, the act had regained its earlier momentum and provided the soundtrack to Spike Lee’s «He Got Game,» which was widely deemed as a comeback album for the hip-hop act.