I would agree with Paul and Uriel to a degree - there is definitely a perceptible aspect of "black voices" that can mark them down as distinguishable from "white" ones, even when the respective accents are quite apparent.
The UK has had two very prominent national broadcasters/TV newsreaders who are absolutely black - Sir Trevor Macdonald and Moira Stuart ( in spite of her THOROUGHLY Scottish name she is black as the Ace of Spades as they say*). Both speak in standard English English RP and if you didn't know who they were, had never seen them before and knew nothing about them at all, and you were to listen to their voices while blindfolded you would assume they were native British white.....snowflakes like me** But....if you concentrated deep and hard and listened accordingly, you would become aware of a really faint hint of what most of us would now recognise as something of the "black" voice as mentioned by Paul and Uriel. It must have something to do with factors governing the way people of certain racial groups vocalise.
The study of social history in the UK tells us that it wasn't until the late 1950s that most of Britain saw black people in the flesh for the very first time in any large numbers, alrthough there were small "colnies" in the larger cities, especially ports such as Liverpool, and it is there where black people still predominate, and spread out across the country as a whole whites form over 90% of the population. In this Parliamentary constituency of Edinburgh West 97.6% of the electorate are white. In some inner city areas of London there are some boroughs where the whites form just 55% of the population.
The UK's Black newsreaders:
An early morning national ITV black newscaster in the UK - familiar face but I don't know his name tbh with you. I think he is a Phil Something or other but I may be wrong. Anyway, to me as a Scot he sounds quite "posh" English English, but can you detect any trace of "blackness"? Close your peepers and see what gets through to you....
http://www.youtube.com/watch?v=hWB1cw_SG38&NR=1
Now here is Sir Trevor Macdonald - most well known of all black newscasters in the UK....do a wee bit of the old shuteye and see what you think....
http://www.youtube.com/watch?v=Dds3k6OcKTU
Moira Stuart - a black former newsreader in spite of her thoroughly Scottish names as I have already said. She is also seen in other programs now and again.......
http://www.youtube.com/watch?v=D1W-HnMQUgk&feature=related
Can you detect any "blackness" in their very British (English English) sounding voices?
Right at the other end of the social and the educational spectrum - or lack of in this case - this black ned (or chav in this case as it is filmed in a poor neighbourhood in England somewhere - ned is what we in Scotland call scroats like this). Now you CAN detect a "blackness" in his voice I reckon. If you were blind I think you would be able to tell that this ned was not white.
From the accents this was definitely filmed in Northern England - North West England in fact, detectable from this scroat's accent and those of the police officers as well - I would safely bet a quid or two that it is in the Manchester area.
http://www.youtube.com/watch?v=-cPNiCST1Ig
PS: please note - none of those police officers carried firearms (guns) - we are very proud of that especially when you consider all our social problems, such as this one so clearly demonstrated here with this highly gobby wee daftie.
Now...another kind of "black" voice - the Metro Ghetto Black Voice - part of the so called urban "gang/rap culture" where there is absolutely no mistaking the "blackness" in the voice especially that of black males, and younger black males in particular - it is a deliberate and conscious decision to sound "black ghetto" and it's as if they have organised their own form of English, distinguishable from any other.
You really don't need to play shuteye here.
Typical black London speak - especially from one of the guys - the one in the middle - a geezer called Bashy. Typical London "ghetto speak" - a deliberate form of speech used as an identifiable "Black lingua franca". This was filmed at the annual Notting Hill street carnival in West London - the largest such event in Europe laasting over the last weekend in August.
http://www.youtube.com/watch?v=NOFRILWbOOo&feature=related
*Spade is a taboo slang term for a black person - now on a par with Nigger - both are banned from acceptable conversation in the UK even though about 50/60 years ago they were used without any comeback at all.
**As with all "-isms" one side of a social divide can say what the hell they like about the other with impunity, but the opposite party has to keep the gob firmly shut and the tongue tightly tied or else the heavens would fall in and it would be the end of civilisation as we know it!
On a late night tube train in South London last year a mate and I could be openly addressed as "snowflakes" by a group of about seven or eight young black youths about five or six years younger than ourselves with no comeback for them at all (apart from us two wading in among these guys with our fists flying ---- as if!) but no way would we have got away with calling them either of the above taboo words, altough the train compartment contained no other people but my mate and I and those scroats as it was heading for midnight anyway, and we were under a very predominantly "black" area of Sahf Landun (that's Sarf Landun for South London) - Brixton or Clapham, I can't remember which.
Anyway, it was a relief for both of us to get to very safe South Wimbledon in the end.