A small-sized audio signal reproducing apparatus for hearing reproduced audio signals with the aid of a headphone is disclosed. Digitized and compression encoded audio signals, stored in a semiconductor memory, are read out so as to undergo a decoding operation, which is an inverse operation to compression...http://www.google.co.uk/patents/US5640458?utm_source=gb-gplus-sharePatent US5640458 - Audio signal reproducing apparatus
