BAH, as far as I understand it, the various members of the Chinese language family all appear related to Middle Chinese (circa 7th century CE; see en.wikipedia.org/wiki/Middle_Chinese), the pronunciation of which can only be reconstructed to a limited extent, because the Chinese characters do not directly indicate pronunciation in the way that phonetically-based writing systems like those using the Roman alphabet (ABC) do. The earliest evidence of pronunciation, other than the phonetic elements within characters, is essentially the QieYun rhymebook
of 601 CE. This reflects the language as spoken at the Nanjing court; Marjorie Chan’s page (deall.ohio-state.edu/chan.9/c681/table1.htm) gives the following: “The standard language of the Northern and Southern Dynasties codified in the Qieyun (601 AD), treated as reflecting the speech of the Nanjing court in the 6th c. (i.e., based on 3rd c. Luoyang speech brought to the Nanjing court).”
Thus, reconstruction of even older Chinese pronunciation becomes quite speculative, and from what I can gather, involves the relationships between sounds more than it does the actual sound values; the rhyming schemes preserved in the Shijing, or Book of Poetry, are one of the few sources I can think of. But they don’t tell us what the actual phonemics were, just which words rhymed at the time, with implications for how the words must have changed. This is very limited information. Thus, the Old Chinese reconstructions are not ‘readable’, if you will, but appear to be jumbles of arbitrarily chosen letters and symbols. And even earlier stages, like the “proto-Chinese” of the late Shang period, are simply so far removed from the Qie Yun (approx. two millennia), that we essentially have no idea what the spoken language of the Shang people sounded like. We also don’t know the extent to which the spoken language of the Zhou people, who adopted the Shang writing system, was related to that of the Shang. So, I’m sorry to say that unless an archaeological miracle unearths the Shang equivalents of the Shijing and Qieyun, we are unlikely to ever know what the language recorded on the oracle bones sounded like.
However, this is not my area of strength, and I’d be very, very interested in reading any corrections to or expansions upon this information. If you’re interested in this general area, you might pick up Norman, Jerry: Chinese. Cambridge University Press, 1988. ISBN 0521296536, and Ramsey, S. Robert: The Languages of China. Princeton University Press, 1987. ISBN 069101468X; both are on my shelf but are not high on my reading list, so I can’t comment on them yet. Regarding how Middle Chinese is reconstructed, you might try:
Middle Chinese: A Study in Historical Phonology
British Columbia University Vancouver 1984
Hardback 290pp ISBN 0774801921.
I’ve ordered it but not received it yet. I’m keen to hear any reactions to the above three books, too.