voicer vs talker

voicer and talker both are nouns.

Word	Noun	Adjective	Verb	Adverb
voicer	Yes	No	No	No
talker	Yes	No	No	No

As nouns, talker is a hypernym of voicer; that is, talker is a word with a broader meaning than voicer:

voicer: a speaker who voices an opinion
talker: someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)

Other hypernyms of voicer include speaker, utterer, verbaliser, verbalizer.

voicer (noun)	talker (noun)
a speaker who voices an opinion	someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)
someone who regulates the tone of organ pipes