Chinese “dialects” are, by European standards, separate language families, like Romance and Germanic. When I was a kid, all the Chinese I heard in Chinatown or in the movies was Cantonese (or other southern languages). Mandarin, especially in the Northern half of the country, sounds very different. Even within Mandarin, with hundreds of millions of speakers, and lots of regional varieties, you can imagine. You could take the exact same words, pronounce them in another Chinese “dialect”, and it would be incomprehensible to the untrained ear. Besides the consonants and vowels, the isochrony is totally different. Since Chinese people weren’t able to travel abroad much when I was a kid, the first time I heard actual Mandarin, you could have knocked me over with a feather — it didn’t sound like “Chinese”. By the way, we could comment more specifically if we knew exactly what sounds sh, zh and kh represented. Is KH an aspirated K, or a spirantized K? ZH is used in the current official romanization as a sound similar to the English J, but you are probably referring to the sound that is currently romanized as R (somewhat between R and SH). In Beijing Mandarin in particular, several different “retroflex” sibilants tend to be reduced to R in rapid speech.