Clear Channel, which dominates the American radio business and is also a major concert promoter, is offering a new deal – go to the concert, then five minutes after it’s finished, buy a recording of the concert you just heard. “Although initially modest, involving only small-audience clubs and theaters in the Boston area, the venture could eventually extend beyond radio and concerts into music distribution. And that could prove troubling to critics, who already complain that the company’s rigidly formatted radio stations prevent diverse artists from reaching the airwaves and that its dominance of the concert business too often forces touring acts to accept unfavorable deals.”