Compact disc duplication is one of methods used to produce mass quantities of CDs. The duplication process is relatively quick, compared to the replication process, with a turnaround of roughly two or three days. This method is used to produce orders of up to 10,000 compact discs. However, duplicated CDs (and even DVDs) may not function in some devices, and often have a slightly different look than replicated CDs, because the process uses pre-made discs.
The duplication process is relatively the same as "burning" a disc from a computer's disc drive. A master CD is inserted into the duplicating device, then the device starts to burn additional discs from the master CD. Some duplicating devices can burn multiple copies at once, as well as print the CD's cover art. Most of the "consumer" available duplicating devices can burn around 500 additional discs per run, while some can do runs into the 1000s of discs.
CD replication is a high-end production method for CD productions. This method typically produces over 10,000 CDs in a single run, and often involves packaging and print, both screen printing and offset, production for the CDs as well. Because of the high volume of CDs there is often a slower turnover time for replication, roughly ranging between seven to 10 days. Replicated CDs work in any device designed to play them.
The replication process starts with a "Glass Master Disc" that contains all of the information that will be contained on all the other discs. This glass master disc is then used to "stamp" the other discs. A layer of reflective material is applied to the additional disc as well as a coating that makes the disc most resilient and durable. The covers of the discs are then printed on top of the reflective material, and the discs are packaged.
While the process for creating the addition CDs varies between duplication and replication, the final product is relatively the same. However, many duplicated discs have limitations that replicated CDs do not, such as player compatibility. Replicated discs also tend to more durable than duplicated discs to stress and the elements. Replicated discs are a better choice for high-volume productions, while duplicated discs are good for short runs.