By now, as far as I can judge, a paradoxical situation has emerged in the field of sound reproduction. Though there are amplifiers and acoustic systems with very good characteristics and even with moderate prices, there is a considerable number of the consumers not satisfied with the result. All the users can be provisionally split into four groups.
Let us consider the death of a person, determined by the effect of marginotomy, as a timely catastrophe; and the sudden death or disability as premature. It is obvious that, using such criteria, the diagnostic value of telemedicine becomes non-zero only in case of the prevention of a premature catastrophe.
Modern low-speed speech codecs provide the satisfactory quality of signal transmission up to the speed of about 600 bps. High speech quality is obtained at the speed of more than 1200 bps, speeds of 200 and less are practically not used, because the intelligibility rapidly falls after the values of about 300 bps.