We are in the process of completing our home theater and are not very experienced in the equipment area. Someone mentioned a "line doubler" to me the other day and I would like some enlightenment on the subject. We are using an older Sony 1020 CRT (Red, Blue, Green) projector and projecting to a 70"x70" screen. We mostly watch dvds on our player which has "progressive scan" but also what some tv on it. Do we need a line doubler ? Will we see a great improvement in the images with one ? I do have a NextVision 5 High Definition Video Processor (still in box), is this a line doubler ? I know these questions may be elementary to some of you "pros" but we are in need of some good advice.