Suddenly another voice spoke, low and melodious, its very sound an enchantment. Those who listened unwarily to that voice could seldom report the words that they heard; and if they did, they wondered, for little power remained in them. Mostly they remembered only that it was a delight to hear the voice speaking, all that it said seemed wise and reasonable, and desire awoke in them by swift agreement to seem wise themselves. When others spoke they seemed harsh and uncouth by contrast; and if they gainsaid the voice, anger was kindled in the hearts of those under the spell.
Maybe Saruman was hiding a TelePrompter in Orthanc.