Sony's ATRAC codec differs from uncompressed PCM in that it is a psychoacoustic lossy audio data reduction scheme and is such that the recorded signal does not require decompression on replay. Although it is intended that the reproduced signal may sound nearly identical to the original as far as the listener is concerned, it differs sufficiently that listening on a high quality audio system will betray the difference – other true compression schemes generally share this characteristic to a greater or lesser degree.