Sample to Sample Accuracy

In audio terms a sample refers to a single element of an audio signal. It contains a value and a duration to represent that signal at that given moment. This Harmony Central article explains the need for sample to sample accuracy in great detail.

To summarise it quickly I have put together a simple example.


The image above shows two audio signals, one on top in green and one on the bottom in yellow. Lets say these signals play together as a section of a song, the top being the drums and the bottom being the bass, continuously looping. It is obvious from the image that the bottom signal is shorter than the top but if you look at the timeline it is actually only shorter by five hundredths of a second - inaudible!

While not noticeable on its own, after these samples have looped a hundred times that discrepancy (shown by the red ) will become one millisecond. Slowly the more each signal loops they will grow further and further out of time. If the signals had the exact same amount of samples then they would NEVER go out of time. This is why sample to sample accuracy is required when dealing with looping audio.