Star Wars Episode 1: The Phantom Menace - How Many Lightsabers Does It Take?!?
In the beginning of Episode I, in the scene after the Jedi Ambassadors' ship was destroyed, Obi-Wan Kenobi and Qui-Gon Jin both ignited thier lightsabers in reflex to sensing imminent danger. If you listen carefully, hear not two, but THREE lightsabers being ignited.
If you notice Qui Gonns mustache is different scences...one minute the middle of it is shaved out and then the next minute it reappears. The other was around. One minute its there then gone...He grows facial hair fast man...
I heard 3 lightsabers power up but I only heard the sound of a lightsaber extending twice. I'm guessing that's what you meant; maybe that first one was some other machine powering up, perhaps even the dioxys generator. We assume that they were alerted to danger solely by a disturbance in the force, but maybe that first sound provided an additional warning.
talie-
What bad guy? If there was one, he would want to be as quiet as possible, besides, who would be dumb enough to try to fight with heavy security, two jedis, and nowhere to go?