let down vs get down

let down and get down both are verbs.

Word	Noun	Adjective	Verb	Adverb
let down	No	No	Yes	No
get down	No	No	Yes	No

As verbs, let down and get down are synonyms defined as:

Other synonyms of let down include bring down, lower, take down.

let down (verb)	get down (verb)
fail to meet the hopes or expectations of	take the first step or steps in carrying out an action
move something or somebody to a lower position	put down in writing; of texts, musical compositions, etc.
	pass through the esophagus as part of eating or drinking
	lower someone's spirits; make downhearted
	move something or somebody to a lower position
	alight from (a horse)
	lower (one's body) as by kneeling