Is there any evidence that implies that accent/dialect prestige is formed due to the sounds of accents (i.e. something to back up statements like an accent being "harsh sounding") or is it really just to do with perceptions of the area in which the accent is spoken in (i.e. if an area has social problems, does the accent that goes with it have a bad image?)
I'm thinking here of areas like Glasgow, Birmingham, Liverpool, Swansea etc. in the UK.
I know of no evidence that aesthetic judgments are involved, and several findings to the contrary.
".. we have in a series of studies investigated the merit of the social connotations hypothesis. ... French Canadians have traditionally favored the Parisian dialect over local forms of French in terms of elegance and pleasantness, just as the Greeks have favored the standard Athenian accent over the Cretan variety. The inherent value hypothesis would propose that English speakers totally unfamiliar with either French or Greek would share these natural preferences. Not so. Our English judges (having, of course, no social connotations associated with these sounds) rated the corresponding and non-standard varieties equally favorably.
"In another study, we asked American and Canadian listeners to rate a variety of British regionally accented speakers whose ratings varied considerably in terms of pleasantness for local British judges. While they were obviously familiar with the language per se (unlike the previous studies), once again they did not discriminate the varieties in terms of pleasantness. ... Cockney, one of the most denigrated British varieties, sounded as fine to the Americans as any other variety."
It's due to social prestige.
Let's look at a simple example from the history of English accents: changing "ng" to /n/ at the end of a word.
Today, a word like "going" is pronounced with an /ŋ/ sound (a velar nasal) in a higher-prestige accent, yet with an /n/ sound "goin" in a lower-prestige accent. Pronouncing "ng" as /n/ is seen as less educated or less formal.
In earlier times, pronouncing "going" as "goin" (with an /n/) was the mark of the English aristocracy. Pronouncing it with an /ŋ/ was more common among the lower classes.(See an article on Language Log for some information about this historical switch.)
How exactly this change came about is actually rather interesting from a historical point of view. The suffix marking verbal nouns (like in "a building") was "-inge" in Middle English, while the suffix marking progressive participles (like in "I'm running") was "-inde". The two merged together in southern England in the 1300s, spreading slowly but never quite taking over the whole English-speaking world.
I believe it's based purely on social prestige.
For example, eastern dialects of Turkish traditionally enjoy a much lower prestige than the standard Istanbul dialect. The uvular/velar fricatives that they have (but that the Istanbul dialect lacks) are particularly stigmatized. But the same sounds, when applied to French or German, have a much higher social prestige in the same country.
I agree with others who say that it is only due to social prestige. A good example of this is English dialects. Standard American English is rhotic, whereas Standard British Englis is Non-Rhotic. If one was more aesthetically pleasing it would predominate in both the UK or the US, which is clearly not the case.
