IR?

I just bought one of those Digital to NTSC converters for my TV. I want to add a second one in the same room but then I'd have a situation where the remote is going to hit both converters. Would it be possible to change the IR detector and emitter in one set to a different wavelength so the remotes don't interact. IS anyone familiar with this. Obviously I'm not. I know there are systems out there that can route the IR but that means another box, another remote and so on, and it would be way easier to just use two different brands of converters. bg