When I was learning the English phonemes, I noticed that the phoneme represented by /z/ was pronounced significantly differently in the two tutorials I had purchased.
I had thought that maybe one of the pronunciation information was wrong, so I wanted to find more sounds so I could figure out which one was wrong.
I found two web pages about English phonemes, and it turned out that the pronunciation on these two sites corresponded to the pronunciation of those two pronunciation materials respectively.
I was confused.
So why are there two different pronunciations?
I made this guess: maybe the two different pronunciations are distinguishable in my language system, but in English the two pronunciations are the same phonemes.
But I am not sure if this is the case or not.