Rattle

possibly pilot bearing? is it hard to shift? does it grind going into gears?

or maybe the throw out bearing? does it go away after the clutch is ALL the way out or after the disc/input shaft have caught up with the flywheel/pressure plate?

EDIT: after re-reading your post, i am going to guess that this is a new noise and is probably not loud enough to diagnose yet. however either of the two bearings would make noise up the entire rev range. Perhaps it is too early to tell?
 
I dont think is throw out bearing cause wouldnt it do it at idle to?
Rattle seems to only come on at certain rpm and i tried to pin point were its coming from..neighbor told me it was just something loose..either a thrust bearing or the fly wheel on the clutch..he had the same problem all he did was tighten the bolts and it went away