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发表于 2013-2-3 21:30:26
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原帖由 farrel 于 2013-2-3 21:20 发表 
白版，THD是模拟部分的。。模拟部分是极其复杂的。
你随便去问问哪个工程师，都和Bladelius先生的结论是一样的，THD不能完全代表音质，我没有任何意见。
但是，Jitter是数字领域的，除了误码，就是Jitter，没有 ...
随手一搜Dan Lavry的采访：(技术说明在http://lavryengineering.com/pdfs/lavry-on-jitter.pdf）
When CD came on horizon nobody talked about jitter. Now days everyone is having his own philosophy around it. Can you elaborate on this subject please. What is the real importance and how to approach this?
Jitter is not only an audio issue. I was dealing with jitter issues in medical conversion, way before the days of digital audio. Jitter is an issue for all conversion (video, instrumentation, telecom, medical, industrial controls…).
The concept of conversion is based on two requirements:
“Taking precise snap shots”
Taking the snap shots at evenly spaced intervals, and playing them back at the same evenly spaced intervals.
Think of a movie camera with an “unsteady motor”, or a playback film projector with a motor that rattles between too slow and too fast. Either case will distort the outcome, and the distortion depends on both the jitter (speed variations), and on the subject itself. Jitter would not do much harm to a steady object, but it does alter the view of a fast moving object. Similarly, in audio, the distortions due to uneven timing (jitter) is due to the interaction between the clock imperfection and the audio itself. Unlike tube, transformer or many other distortions, the outcome due to jitter is NOT predictable or repeatable. There is no such thing as “good sounding jitter”. There are many types and causes of jitters. What we hear is not only about the jitter amplitude and frequency. It is also about jitter type.
就在说What we hear is not only about the jitter amplitude and frequency. It is also about jitter type.
所以，单个数字无法准确的描述JITTER的特征.！
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楼主
发表于 2013-2-3 22:09:51
