Not much, in fact I think it's significantly better than MP3 or any other lossy compression methods, due to it covering the full range of the spectrum.
But, the SNR is very, very poor. Due to the 4-bit coding, it needs to rely on quantisation to fill the remaining data in, which is an imperfect process.
leo @'d me in a thread about his last dream, stating he was passionately making out with a guy he used to know and then woke up while reaching for his crotch, and said that i would "know who 'tf' it is"
and of course i know, it's luke