'There are a number of circumstances where oversampling may, in theory, provide benefits. One thing of note is that there is a significant difference in the accuracy of the math required to do synchronous sample rate conversion and asynchronous sample rate conversion. An example of synchronous sample rate conversion is the type used in modern AD and DA converters. The sample rate is “multiplied” by an integer amount 2, 4, 8, or 16 times the original frequency.Asynchronous sample rate conversion is used to go between two frequencies that are not an integer multiple of each other, and requires much more complex computing to do well. (like going from 96 to 44.1).Converter technology has evolved over time to the present day to utilizing a “low bit” converter (2-4 bits) operating at a very high sample rate, then “doing math” on the output to trade-off more bits for a lowert (output) sample rate. The result is an accuracy that cannot be achieved with older converter technology that operates at the output sample rate, and eases the requirements for the input/output filters(unlike the implementation in earlier designs which caused undesirable side effects such as high-frequency roll-off and phase distortion) Asynchronous sample rate conversion is a convenient way to bypass the issue of “tying” two devices together that are communicating digital audio data, but if not done well can degrade the quality of the signal. If done properly at the appropriate time, “oversampling” can actually help achieve audio quality that cannot be achieved by any other means.
Topic: What do you use as a DAC? (Read 14083 times)