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ลำโพงแบบ Current drive เป็นยังไงครับ?

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ออฟไลน์ JUUD

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ผู้แต่งอาจจะเป็นนักทฤษฏีที่เอาวิทยานิพนธ์ปริญญาเอกมาแปลงเป็นหนังสือ     ต้องรอดูผลงานในภาคปฏิบัติ
ผมว่าถ้าแกผลิตแอมป์ที่มีความซับซ้อนมากๆเพื่อมาควบคุมกระแสและโวลพร้อมๆกัน ผลในทางทฤษฏีและปฏิบัติจะเหมือนกันหรือเปล่าก็ไม่รู้   
ผมอยากเชื่อนักปฏิบัติอย่าง Nelson Pass, John Curl, Mark Levinson,Bills Johnson(Audio Research) มากกว่า


ออฟไลน์ Martra

  • www.vonorfivestars.com
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In current-drive design, impedances are not matched, but the output impedance and the impedance seen by the drivers is kept as high as possible. With infinite output impedance, there is not necessarily need to "match" amps with speakers any more than there is such need in voltage drive. Note also that the nominal impedance of the output taps is a different thing than the output impedance.

แปลมาบางส่วนครับ....

ในการออกแบบ Current Drive นี้จะไม่มีการแมทชชิ่ง อิมพีแดนซ์ แต่ อิมพีแดนซ์ขาออก และอิมพีแดนซ์ที่ถูกมองเห็นจาก ดอกลำโพง
จะถูกจับให้สูงเท่าที่จะสูงได้.....ด้วยอิมพีแดนซ์ขาออกที่ไม่สิ้นสุด มันไม่มีความจำเป็นต้องมานั่งจับคู่แมทช์อิมพีแดนซ์ แบบลำโพงปัจจุบัน

 :D
Vinyl Sound = Toe Tapping and Heaven on Earth...:dj


ออฟไลน์ Martra

  • www.vonorfivestars.com
  • Super Star
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    • กระทู้: 1,390
    • เพศ:ชาย
  • "One Stop Solution for Bed and Bedding Products"
    • http://www.vonorfivestars.com
พอดีไปเจอลิงค์ ผู้เขียนอ้างว่า คอนเซทป์ ลำโพงแบบที่ใช้อยู่ ยังมีข้อเสียอยู่เยอะมาก....

http://www.current-drive.info/

พี่น้องท่านใด มีความเห็นยังๆไง แบ่งปันกันหน่อย....ส่วนผม ฟังอย่างเดียว.... :D

หนังสือที่แกพึ่งวางขายเกี่ยวกัย คอนเซทป์ลำโพงนี้ ....เค้าบอกว่า ถ้ายังไม่มีใครทำขาย...อีกสองสามปี
แกจะผลิตเองเลย.... :drive1  d_d
http://www.audiocircle.com/index.php?topic=73767.0

Introduction:

Why have the basic laws of electrodynamics been ignored in the design of all loudspeaker operations? A frank exposure of the flaws of voltage drive and a thorough, groundbreaking guide to the only physically justified way of operating electrodynamic loudspeakers - current-drive. The author argues that the sound quality of virtually all existing speaker systems has been severely impaired by the manifoldly indefinite electromotive forces induced in the voice coil, that corrupt the flow of current; and what's dramatic - the measurable evidence is plain and overwhelming! These inherent EMFs in themselves can never be suppressed by any kind of amplifier, but their detrimental effect on current and hence on sonic performance can be eliminated by adequate source impedance. Thus, the secret of valve amplifiers also becomes apparent. Written for all from the academic community to lay hobbyists. Besides new concepts for amplifier and speaker design and demonstrative projects, the book also features novel ideas for modelling, filter design, measurements, and protection; and a useful tutorial on analogue linear systems. For more details, visit www.current-drive.info.

From the back cover:

Is it indeed possible that all audio power amplifiers of the world operate and have operated since their inception - on an all wrong principle? Is it also possible that the sonic aberration caused by this gross technical mistake has substantially impaired our experience with loudspeaker-produced sound, with implications even on the musical evolution of our civilization?

According to laws of physics, electric current is that which in a speaker driver effects diaphragm acceleration, which in turn produces sound pressure. Yet all power amplifiers strive, even tooth and nail, to control the voltage at the loudspeaker terminals, which only indirectly affects the current flowing in the voice coil.

Current-controlling loudspeakers is nevertheless not an all-new concept. Some of the benefits it brings, like decreasing of harmonic distortion and expanding of frequency range, have been known at least by specialists. However, there prevails great ignorance about the many disastrous interference mechanisms that traditional voltage drive inevitably creates and that are fully or partially eliminable by correctly operating current-drive. Also, current-drive does not necessitate active speakers any more than voltage drive does, but amazing improvement in sound quality is achievable by simple means. Based on properties of linear systems and investigation, plenty of other flawed conceptions prevalent in the field of audio technology are also pointed out.

When writing this, virtually no full-range audio equipment operating on the current-principle has yet been seen on the market. One reason may be that controlling the resonance of the bass driver under current-drive has been considered difficult. To resolve this, new handy techniques and circuits are introduced, so that technical obstacles for the extensive utilization of the current-principle are cleared away. Also, it is shown that so-called electrical damping, that pertains to voltage drive, is actually a totally invalid argument for the choice of the driving method.

The book has been written out with easy-to-understand language for both professionals and interested laymen, so the novel amplifier and loudspeaker realization concepts are made available to all. An ordinary circuit simulator can be used also for predicting the acoustic response, without need for special software. In the appendices is provided valuable basic knowledge about analogue systems.
Vinyl Sound = Toe Tapping and Heaven on Earth...:dj