CD5400 Original Special Edition (OSE) CD player is the Marantz self-tuned version of the CD5400. To dramatically improve the sound quality, all the components are criticallyexamined, after which it is possible to determine where customisation is needed. At the end of this detailed process the power supply lines are enforced and the audio circuitry is tremendously tweaked up. This custom treatment gives a much more consistent response in entire frequency range. Musical reproduction is characterized by improved transparency and image, as well as tonal accuracy.