noise level vs amplitude

noise level and amplitude both are nouns.

Word	Noun	Adjective	Verb	Adverb
noise level	Yes	No	No	No
amplitude	Yes	No	No	No

As nouns, amplitude is a hypernym of noise level; that is, amplitude is a word with a broader meaning than noise level:

noise level (noun)	amplitude (noun)
the amplitude level of the undesired background noise	greatness of magnitude
	the property of copious abundance
	(physics) the maximum displacement of a periodic wave