trumpet vs let loose

trumpet is a noun but let loose is not a noun.

Word	Noun	Adjective	Verb	Adverb
trumpet	Yes	No	Yes	No
let loose	No	No	Yes	No

As verbs, let loose is a hypernym of trumpet; that is, let loose is a word with a broader meaning than trumpet:

Other hypernyms of trumpet include emit, let out, utter.

trumpet (noun)	let loose (noun)
a brass musical instrument with a brilliant tone; has a narrow tube and a flared bell and is played by means of valves

trumpet (verb)	let loose (verb)
proclaim on, or as if on, a trumpet	express audibly; utter sounds (not necessarily words)
utter in trumpet-like sounds	turn loose or free from restraint
play or blow on the trumpet