A system for enhancing a signal regenerated from an encoded audio signal. The system comprises a decoder arranged to receive the encoded audio signal and produce a decoded audio signal, a feature extraction means arranged to receive at least one of the decoded and encoded audio signal and extract at least one feature from at least one of the decoded and encoded audio signal, a mapping means arranged to map the at least one feature to an enhancement signal and operable to generate and output the enhancement signal, whereby the enhancement signal has a frequency band that is within the decoded audio signal frequency band, and a mixing means arranged to receive the decoded audio signal and the enhancement signal and mix the enhancement signal with the decoded audio signal.