Within Chinese languages and dialects how does Z and X differentiate?

Strictly speaking, Chinese doesn’t have X and Z. Westerners have come up with several different systems for writing Chinese using the Roman alphabet, but there’s quite a bit of disagreement among the different systems about which Roman letters best represent certain Chinese sounds.

For instance, in the Hanyu Pinyin system, you’ll see lots of “X“s. The Wade-Giles system will use “hs” to represent that same sound, and the Gwoyeu Romatzyh system will use “shi”.

Where Hanyu Pinyin uses “z”, Wade-Giles uses “ts” and Gwoyeu Romatzyh uses “tz”.

And that’s just three of the commonly used systems. There are plenty of others. All of them are just coarse approximations of the actual Chinese pronunciations.

It’s completely different sounding.

@thorninmud has given a decent answer.

In general:

X sounds like hs-, ie an aspirated s- sound… or a SOFT sh-
(try saying sh- with your tongue held further back, and teeth held apart)
basically, breathe out purposefully, whilst making an s- sound.

Z can sound like ts-, when its on its own… or j-/soft ch-, when as zh.
e.g. Mao Zedong sounds like Mao Tse-tng, but Guangzhou, sounds like Gw’ng-jaoo
(but very clipped, with a hard j, not like how a typical American would pronounce that)

The best way to find out would be to find audio clips of relevant words, or ask a mainland Chinese person to say it for you.

I’ve come to realise there really is no effective way of describing the sounds of Chinese using the Latin alphabet. I think Pinyin is great, but as I’m sure you realise, you have to first know what sounds the letters actually stand for, before being able to use it. There’s only a rough correlation with the English sounds.