well depends yerss, I don't know anything about cloning so this has no scientific fact, but I think if u clone someone u take over all the physical aspects so I believe voices should be identical unless something altered the physical aspects
(also lemme bring in my that I knowvery lil' of biology (ask yerss 😄))
so if voice has anything to do with mental aspects then I think they could have a different voice cause I think if u clone a person they have a different mind
It doesn't make sense. It is nonsense. We have absolutely no reason to think they would clone clones, and in any case the difference in voices, judging by the perfection of the originals (which makes any attempt to use real-world science in this case as laughable as with anything else in Star Wars) would be minute regardless if the Stormtroop[ers can be considered true clones in any way.
And in any case the clear intimation of the GL quote is that they are cloned just as the Clonetroopers are.