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主題: Phase (相位)

  1. #21
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    phase

    In electronic signaling, phase is a definition of the position of a point in time (instant) on a waveform cycle. A complete cycle is defined as 360 degrees of phase as shown in Illustration A below. Phase can also be an expression of relative displacement between or among waves having the same frequency .
    Phase difference , also called phase angle , in degrees is conventionally defined as a number greater than -180, and less than or equal to +180. Leading phase refers to a wave that occurs "ahead" of another wave of the same frequency. Lagging phase refers to a wave that occurs "behind" another wave of the same frequency. When two signals differ in phase by -90 or +90 degrees, they are said to be in phase quadrature . When two waves differ in phase by 180 degrees (-180 is technically the same as +180), the waves are said to be in phase opposition . Illustration B shows two waves that are in phase quadrature. The wave depicted by the dashed line leads the wave represented by the solid line by 90 degrees.
    Phase is sometimes expressed in radians rather than in degrees. One radian of phase corresponds to approximately 57.3 degrees. Engineers and technicians generally use degrees; physicists more often use radians.
    The time interval for one degree of phase is inversely proportional to the frequency. If the frequency of a signal (in hertz ) is given by f , then the time t deg (in seconds) corresponding to one degree of phase is:
    t deg = 1 / (360 f )
    The time t rad (in seconds) corresponding to one radian of phase is approximately:

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  3. #22
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    很多人會讓很簡單的解釋,東拉西扯一堆毫無關連的東西,讓它變得很複雜

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  5. #23
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    產品設計、空間是另外一回事,正常要怎麼做才會讓喇叭及器材相位一致呢?

    咱們一個一個講.....

  6. #24
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    我跟唸書時代一樣,從頭看起...

    What is phase?

    Phase is a frequency dependent time delay. If all frequencies in a sound wave (music, for instance), are delayed by the same amount as they pass through a device, we call that device “phase linear.” A digital delay has this characteristic—it simply delays the sound as a whole, without altering the relationships of frequencies to each other. The human ear is insensitive to this kind of phase change of delay, as long as the delay is constant and we don’t have another signal to reference it to. The audio from a CD-player is always delayed due to processing, for instance, but it has no effect on our listening enjoyment.

    http://www.earlevel.com/main/1996/10...tion-of-phase/

  7. #25
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    這麼快就急著要答案,果然是有錢人

    我都自己來
    1. 先弄清楚何謂相位
    2. 相位對聲音的影響
    3. 如何量測或聽出相位問題
    4. 如何解決相位問題

    引用 作者: AndyChu 查看文章
    產品設計是另外一回事,正常要怎麼做才會讓喇叭及器材相位一致呢?

  8. #26
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    引用 作者: AndyChu 查看文章
    產品設計、空間是另外一回事,正常要怎麼做才會讓喇叭及器材相位一致呢?

    咱們一個一個講.....
    除非能夠排除活塞運動 不然相位永遠不可能一致吧.......

  9. #27
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    我是在說懂這麼多,你到最後做的事情都是一樣的.........直接一點算了

    設計跟空間比較複雜,器材及喇叭在沒有其他因素下,要如何擺設及檢查

    引用 作者: 小葉 查看文章
    這麼快就急著要答案,果然是有錢人

    我都自己來
    1. 先弄清楚何謂相位
    2. 相位對聲音的影響
    3. 如何量測或聽出相位問題
    4. 如何解決相位問題

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  11. #28
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    之前小葉給的判定極性的測試, 我用電腦喇叭完全聽不出來, 全部瞎猜......

  12. #29
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    2007-05-23
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    唉唷....我是說在基本的發聲基礎下啦.......動起來當然亂七八糟的

    很多變數不能控制,偏偏大家愛討論這些不能控制的,咱們講一些能自己控制的.....

    東西買回來了,什麼是該做的。

    引用 作者: chsiang 查看文章
    除非能夠排除活塞運動 不然相位永遠不可能一致吧.......

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  14. #30
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    資料~~~~~~~~~~~~~~



    玩了半輩子的音響 世間喧嘩 不如孤獨 寧靜 思想 深山幽谷中的一股清泉

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