I have a different experience. I have a C'dale Synapse Carbon 3 and it had an alum stem and bars and it vibrated, no doubt. I recently put on a FSA OS-99 CSI carbon stem and K-Force carbon handlebar and the high frequency vibration is gone. I will say there's a low freq vibration but it's not nearly as bothersome as the high freq. It wasn't a cheap solution (it's will eventually end up on my SuperSix for weight savings), and there's a potential issue with the handlebar tops angle I'm working with FSA on (but that's another post), but it worked for me. Hope that helps.