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Summary
Description2-bit resolution analog comparison.png
English: 2-bit resolution with four levels of quantization, compared with an analog sine wave. Corrected from five level image in source: Hodgson, Jay (2010). Understanding Records, p.56. ISBN978-1-4411-5607-5. He adapted from Franz, David (2004). Recording and Producing in the Home Studio, p.38-9. Berklee Press.
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Removing stairstep misrepresentation of audio signal which is a graphic anomaly, not how the signal behaves in the real world. Substituting discrete time sample points.