Here’s some reading. Seems that timbral identification and speech are related.
References:
Eimas, P. D., Siqueland, E. R., Jusczyk, P., & Vigorito, J. (1971). Speech perception in early infancy. Science, 171(3968), 303-306.
Kuhl, P. K., & Miller, J. D. (1978). Speech perception by the...