Pretty darn close.
Originally Posted by pierods
I have some Tri-X negs that date from the late 1950's or very early 60's. If you compare scans from the vintage negs to modern Tri-X the look is very similar.
The new version is finer grained, that's for certain, but the shape and character of the grain is very much the same. The overall fingerprint is very, very similar. The vintage negs are a lot thicker and a slightly different shade of gray. I believe the old negs were processed with a developer that dissolved grain and the contrast is a little lower so, it's not an exact comparison, but close.