consonant vs speech sound

consonant and speech sound both are nouns.

Word	Noun	Adjective	Verb	Adverb
consonant	Yes	Yes	No	No
speech sound	Yes	No	No	No

As nouns, speech sound is a hypernym of consonant; that is, speech sound is a word with a broader meaning than consonant:

consonant: a speech sound that is not a vowel
speech sound: (phonetics) an individual sound unit of speech without concern as to whether or not it is a phoneme of some language

Other hypernyms of consonant include phone, sound.

consonant (noun)	speech sound (noun)
a speech sound that is not a vowel	(phonetics) an individual sound unit of speech without concern as to whether or not it is a phoneme of some language
a letter of the alphabet standing for a spoken consonant

consonant (adjective)	speech sound (adjective)
in keeping
involving or characterized by harmony