vocalist vs vocalizer

vocalist and vocalizer both are nouns.

Word	Noun	Adjective	Verb	Adverb
vocalist	Yes	No	No	No
vocalizer	Yes	No	No	No

As nouns, vocalist and vocalizer are synonyms defined as:

Other synonyms of vocalist include singer, vocaliser.

vocalist (noun)	vocalizer (noun)
a person who sings	a person who sings
	an organism that can utter vocal sounds