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Non-backward compatible.


Non-backward compatibility
A new coding standard is non-backward compatible with an existing coding standard if existing decoders (designed to operate with the existing coding standard) are not able to continue to operate by decoding all or part of a bitstream produced according to the new coding standard.


Non-tonal component
A noise-like component of an audio signal.


Nyquist sampling
Sampling at or above twice the maximum bandwidth of a signal.