Blu-spec

Blu-spec is a mastering and manufacturing process developed by Sony Music Entertainment for audio CDs. It aims to produce CDs with a quality closer to the original master recording by utilizing Blu-ray disc manufacturing technology.

The key improvement lies in the use of a blue laser during the mastering process. Unlike traditional CD mastering that uses a red laser, Blu-spec utilizes a blue laser with a shorter wavelength. This shorter wavelength allows for more precise cutting of the pits and lands on the CD master disc. This greater precision in mastering is then carried over to the manufacturing of the CDs.

The Blu-spec process results in CDs with reduced jitter and improved signal-to-noise ratio compared to standard CDs, leading to a clearer and more detailed audio reproduction, according to Sony. Importantly, Blu-spec CDs are playable on standard CD players, requiring no special equipment. It is a physical disc format, not a file format or a new type of encoding.

Blu-spec CDs are often marketed as a premium audio product. A later version, Blu-spec CD2, further refines the process for even greater accuracy in the mastering and replication.