2 x Single= 1 x Dual

There are many more types of single opamps available than dual or quad versions. Not only can it sometimes be interesting to replace a dual opamp by two equivalent single opamps, it also allows the use of two completely different types of opamp, depending on the application. One example is the combination of the DAC and output filter of a CD player. A dual opamp is sometimes used here, although a fast linear amplifier is needed for the current-to-voltage converter, while a good low-noise opamp is more suitable for the output filter.