TEHRAN — As the music ended and the crowd rose in a standing ovation, several women in the audience could be seen with heads bared, the obligatory head scarves draped around their necks.

This was no underground concert by an indie band in North Tehran, though. Rather, it was a recital by a classical lute player in Vahdat Hall. As the opera house emptied, the women casually slipped the scarves back on and walked out. No one seemed to care, or even to notice. MORE