audio vs sound recording

audio and sound recording both are nouns.

Word	Noun	Adjective	Verb	Adverb
audio	Yes	No	No	No
sound recording	Yes	No	No	No

As nouns, audio and sound recording are synonyms defined as:

Other synonyms of audio include audio recording.

audio (noun)	sound recording (noun)
the sound elements of television	a recording of acoustic signals
a recording of acoustic signals
an audible acoustic wave frequency
the audible part of a transmitted signal