Some new CD recorders offer “running OPC” that is advertised as a necessary feature. If this is true, how did older recorders work without it?
Running OPC, also known as continuous OPC, can be an advantage if it is used only to compensate for media problems. If it is used instead to compensate for deficiencies in the recorder, then such a system may be inferior. Prices of CD-R writers have dropped far and fast. The first recorders were priced in the tens of thousands of dollars range. Competition forced prices down to thousands of dollars, then to hundreds of dollars. Diminishing quality has been evident, as volume and technology supported some, but not all, of the price decreases. Since CD-R discs from different manufacturers or various lots may each have unique recording characteristics, every disc is required to have a special 22.5 second long Power Calibration Area, or PCA, for Optimum Power Calibration, or OPC. This region is located before lead-in, and cannot be accessed by a CD-ROM drive. One hundred partitions are located in this region, and one partition is accessed by a CD-R writer before each recording session. The
