high quality vs quality

high quality and quality both are nouns.

Word	Noun	Adjective	Verb	Adverb
high quality	Yes	No	No	No
quality	Yes	Yes	No	No

As nouns, quality is a hypernym of high quality; that is, quality is a word with a broader meaning than high quality:

Other hypernyms of high quality include caliber, calibre.

high quality (noun)	quality (noun)
the quality of being superior	an essential and distinguishing attribute of something or someone
	(music) the distinctive property of a complex sound (a voice or noise or musical sound)
	a degree or grade of excellence or worth
	a characteristic property that defines the apparent individual nature of something
	high social status

high quality (adjective)	quality (adjective)
	of superior grade
	of high social status