The sentences below are from a book and the topic is the difference between the sounds of th and s. Would you explain the difference between the distinction and the contrast in this context? I look them up, of course, but had no clue. It even seems like a matter of taste.

"Okay," I said. "Sure, I can hear it."

"You can her what, the distinction? The contrast?

Thank you,

I don't know what the original author means in context. Distinct = something you can tell apart. Contrast is used in comparison, that you contrast something with one or more other things. So, th and s are distinct sounds. If you are comparing them, you could suggest that someone focuses on the contrast between them.
I suspect, however, that the writer may have merely included two terms whose meanings overlap, as we often do in conversation to lubricate communication: Did you watch that show, that movie, on TV 12 last night?
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Thank you people for the reply.

So, Mister Micawber, the sentence does not mean:

"You can hear what, the distinction? Or, the contrast?"

Sorry I bother you but I wanted to make sure.

Thank you,

I have no idea for sure. I'm just saying that it may not be intended as two different concepts. There is no way of judging without a greater context that makes the thrust of the speaker's utterance clear.
I see.

Thank you for the reply, it was a very helpful tip.

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