  I think there is a difference in Adelaide where the accent sounds closer to the New Zealand accent than in other parts of Australia. The number six sounds like the NZ sux. There is also a distinctive immigrant accent depending on parentage. The accent is maintained by locally born descendants. So you have a clearly recognisable  Lebaness, Greek, Italian etc Australian accent. Also the Sydney Westie and Melbourne Bogan accents are clearly identifiable. These may be more socio-economic than regional however.  