twang vs throb

twang and throb both are nouns.

Word	Noun	Adjective	Verb	Adverb
twang	Yes	No	Yes	No
throb	Yes	No	Yes	No

As verbs, throb is a hypernym of twang; that is, throb is a word with a broader meaning than twang:

twang (noun)	throb (noun)
exaggerated nasality in speech (as in some regional dialects)	an instance of rapid strong pulsation (of the heart)
a sharp vibrating sound (as of a plucked string)	a deep pulsating type of pain

twang (verb)	throb (verb)
pronounce with a nasal twang	tremble convulsively, as from fear or excitement
pluck (strings of an instrument)	expand and contract rhythmically; beat rhythmically
sound with a twang	pulsate or pound with abnormal force
cause to sound with a twang
twitch or throb with pain