Sound Varieties: Rules for Varying Ranges

[fxdung]

It seems that a sound (eg aa, ah, ih...) has a variable range of sound.I know that the before is affected by the follow, eg ''d" in do and did are different. Are there any other rules for the variation range?

 

[berkeman]

It seems that a sound (eg aa, ah, ih...) has a variable range of sound.I know that the before is affected by the follow, eg ''d" in do and did are different. Are there any other rules for the variation range?

Sorry, what?

 

[fxdung]

I mean eg one vowel is not the same when we pronounce may time or by many people or by different contexts

 

[pinball1970]

It seems that a sound (eg aa, ah, ih...) has a variable range of sound.I know that the before is affected by the follow, eg ''d" in do and did are different. Are there any other rules for the variation range?

In English? All letters, vowels, consonants, etc vary depending where in the world you are.
In English the 'd' in do and did are the same.
'Do' will sound different in English depending where you are in England.
Can you be specific about what it is you are asking?

 

[DennisN]

It seems that a sound (eg aa, ah, ih...) has a variable range of sound.I know that the before is affected by the follow, eg ''d" in do and did are different. Are there any other rules for the variation range?

I can't answer the particular question, but it seems you are asking about phonemes.

See e.g. :

https://en.wikipedia.org/wiki/Phoneme
https://en.wikipedia.org/wiki/Phonology