Any sound can be mathematically factored into the product of a slowly varying envelope (also called modulation), and a rapidly-varying fine time structure (also known as carrier). Our goal is to find out which of the two factors, envelope or fine structure, is the most important for auditory perception. To do so, we synthesize novel stimuli which have the envelope of one sound and the fine structure of another sound. We call these stimuli "auditory chimeras" by analogy with the mythological beasts which have the head of a lion, the body of a goat, and the tail of a serpent.
(from: http://research.meei.harvard.edu/chimera/index.html)
This is a python implementation of chimera synthesis, as originally implemented by Bertrand Delgutte in matlab.
python setup.py install
see jupyter notebook for a usage example