Fallen Embers is right about all the V and Odyssey stuff. Those are good observations. I've also noticed that same delay effect on Candlelight fantasia, Odyssey, and Premonition.
Another really cool symbolic thing that always stood out to me in Symphony X songs is the lyrical change and voice change that takes place in Egypt. The main chorus "Gaze in these eyes my child and see, here by my side your destined to be... Fears in the night, flee with the sun, when we are one! Kingdom of gold will lay at your feet, ruler of time and space you will be. Rivers of truth, forever will run, when we are one!!!" in his normal voice changes to
"Gaze in these eyes my child and see, here by my side your destined to be... Fears in the night, chasing with the sun, now we are one! Kingdom of gold now lay at my feet, ruler of time and space I will be. Rivers of lies, forever will run, now we are one!!!" in a more evil and demon like voice.