Whereas bling and blingbling refer to the imaginary sound that is produced by the internal refraction of light in cut diamond, blang and blangblang refers to sound of light refracting inside QVC's Diamondite. blangblang is mainly used as an ironic substitute for blingbling- a phrase now favored by the mtv generation.
Oh my godlessness! That Sinitta remix is so blangblang.