fidelity vs faithfulness

fidelity and faithfulness both are nouns.

Word	Noun	Adjective	Verb	Adverb
fidelity	Yes	No	No	No
faithfulness	Yes	No	No	No

As nouns, fidelity and faithfulness are synonyms defined as:

fidelity (noun)	faithfulness (noun)
the quality of being faithful	the quality of being faithful
accuracy with which an electronic system reproduces the sound or image of its input signal