amplify vs heighten

amplify and heighten both are verbs.

Word	Noun	Adjective	Verb	Adverb
amplify	No	No	Yes	No
heighten	No	No	Yes	No

As verbs, heighten is a hypernym of amplify; that is, heighten is a word with a broader meaning than amplify:

Other hypernyms of amplify include compound, deepen, intensify.

amplify (verb)	heighten (verb)
increase in size, volume or significance	increase the level of
increase the volume of	become more extreme
exaggerate or make bigger	make more extreme; raise in quantity, degree, or intensity
to enlarge beyond bounds or the truth	make more intense, stronger, or more marked
	make (one's senses) more acute
	increase the height of