There are several things that separate modern Humans (Homo Sapiens Sapiens) from Homo Neanderthalensis. One is that Neanderthals had a large brain case and and believed to have a slightly larger brain than we do. Secondly they had a more robust build, so they were stockier and heavier than modern humans. Lastly they are believed to have very different speaking voices than we do, based on what is known about the shape of their vocal tracts. Their speaking voices might have sounded more raspy and almost like wheezing to compared to our voices.
