Digital information is recorded by sampling at a specific or pre-programmed rate. Sample rate converters change sample rates of different kHz (kiloHertz) from one rate to another rate.
These data converters prevent any alteration in speed and pitch from occurring during the transfer of sound recordings from one system application to another. These converters change the rate of a discrete signal to produce a new discrete representation of the continuous underlying signal during transmission of data.
There are two main types of sample rate converters: synchronous converters and asynchronous converters. Synchronous converters convert data between two fixed sampling rates where the rate change is of a similar ratio such as 4, 8 or 32. Asynchronous converters are used when input and output rates are not fixed by a common clock or an exact frequency ratio.
Sample rate converters are used in broadcasting applications, audio/visual devices and high-end consumer products with different frame rates and image scales. Their aim is to maintain the quality in audio and video output across devices.