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CD Recording FAQ
4. CD-R media
4.1. Brands and colours
CD-R media come in many variations. The colour of the reflective surface is the first difference to notice among different brands.
The dye used is the reason for this characteristic colour. The dyes used are based on cyanine, pthalocyanine and, more recently, metal azo. Cyanine and metal azo media are blue, pthalocyanine media are golden or silverish. Some older media were also green, and there are black media for Playstation enthusiasts, though these are rarely found.
Cyanine media are often cheaper than pthalocyanine ones, and there have been speculations that they have a shorter life span and lower performance. However, these speculations have never been based on real facts and there are many cyanine media of superior quality.
CD-R media come in hundreds of different brands, but the original manufacturer is not always the one who packages the media under his brand. There are some manufacturers who produce cdr media, and these sell their products under their brand or sell them to other companies who brand them as theirs. Sometimes a manufacturer may brand products of another manufacturer, for example when his own production is not enough to cover the market needs.
For example, Philips media are not manufactured by Philips. However, Philips has examined products of various manufacturers and has made a contract with some of them to brand their products as "Philips". This practice is often followed by hardware manufacturers, like Teac and Yamaha, who brand media under their name. Usually these media are certified by the hardware manufacturer to work 100% with the hardware under the same name and offer some assurance to users who are confused by the vast variety of media available in the market.
An another example are manufacturers like TDK and Ricoh. These companies manufacture their own cds, but often brand media made by other manufacturers, for example Ritek or Maxell, as theirs.
Any blank cd (and this includes "audio only" and cd-rw media too) includes a header called ATIP which includes information about the real manufacturer, the dye used, the nominal capacity as defined by the manufacturer and the speed rating. These days, the speed rating is left is usually left blank, except the case of cd-rw media.
ATIP can be read even after the media has been written onto and is used by the recorder in order to determine its recording policy. However, some times some of its fields (except the nominal capacity and the dye ones) are left intentionally blank.
ATIP can be read by inserting the media into the recorder and interrogating the drive. Many programs are able to retrieve this information, providing knowledge of the real media manufacturer and the dye used.
On the other hand, media made by the same manufacturer but branded under different names are not always of the same quality. The quality of the coating of the upper surface of the media is also important and plays a significant role in keeping data safe.