The difference between CD duplication and replication

Optical disc duplication involves burning CDRs or DVDRs and optical disc replication involves the manufacture of CDs or DVDs from raw polycarbonate where the data is stamped onto the discs as an exact replica off the original source.

Replication involves the creation of a glass master. The glass master is a physical representation of the original data. Stamps are then created from the glass master, which are then used to “stamp” the data onto the polycarbonate disc surface.

The duplication process involves the creation of a master CDR from the original data at a slow burn speed to avoid any errors. The master is then loaded into a duplication tower where multiple duplicates of the master are burned onto blank CDRs.

The data side on a replicated CD will almost always be silver and on a duplicated CDR a silvery green colour; however there are CDRs available with silver or black data sides if required.

Which type is best?

A replicated disc is generally regarded as the best type of disc available for quality and playback compatibility, however they come with a minimum order of 500x units and take around 7-10 working days to manufacture so they are not suitable for small runs or when the discs are needed in a hurry.

To duplicate or replicate?

As a rule of thumb if the discs are required quickly or the quantity is less than 500 units then the duplication route is taken. On the other hand if turnaround time is not an issue or volumes are higher than 500 units then the best option is usually replication.
Replicated discs are usually used for mass produced commercial releases and duplication is usually used for smaller runs or promotional proposes.
Short run duplication is becoming a more and more popular option for independent artists and labels that want to release hundreds rather than thousands of discs.