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本帖最后由 michael_kg 于 2020-5-31 16:04 编辑
给518兄的专业解释配张Headfonics的图吧,关于DSD/PCM的量化噪声的频谱,方便烧友讨论。注释还是只有英文的,不过518兄已经解释得很清楚了,应该不用翻译了。
For PCM, quantization noise is evenly distributed across range 0 … [sample rate]/2.
For DSD noise is pushed to inaudible (high) part of the spectrum. For pushing (noise shaping) significant energy of noise out of the audible range you need a reserve of the band. I.e. higher sample rate, than for PCM, is needed.
PCM quantization noise correlates with useful signals: no signal equals no noise. DSD noise does not depend on signal and is present in silence also. DSD DACs eliminate this noise.
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