Encode-Decode Noise Reduction (NR) Systems
In this chapter we will discuss methods of compressing (encoding) a signal before it is recorded, and expanding (decoding) it when it is played back. In this manner, the compressed signal can be kept above the noise level of the recording medium. If the tracking of the playback expansion action is the inverse of the compression action, then the original dynamic relationships in the program will be kept intact. In the process, however, the recorder’s noise floor will be modulated by the expansion action.
KeywordsNoise Reduction Tape Recorder Noise Floor Gain Curve Noise Modulation
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