baritone vs low-pitched

baritone is a noun but low-pitched is not a noun.

Word	Noun	Adjective	Verb	Adverb
baritone	Yes	Yes	No	No
low-pitched	No	Yes	No	No

baritone (noun)	low-pitched (noun)
the second lowest brass wind instrument
the second lowest adult male singing voice
a male singer

baritone (adjective)	low-pitched (adjective)
lower in range than tenor and higher than bass	used of sounds and voices; low in pitch or frequency
	set at a low angle or slant