发帖來深入谈一谈Jeff Rowland Class D数字功放

激光鼠

好几家公司提供数字功放的解决方案，Jeff用ICEpower的，我看网上的对ICEpower的东西一个评价：
I have a 2x250Watt icepower in my system right now - it has a well build dual mono PSU, and a special regulated psu for the driverstage of the ICEpower - wery well build with nice psu caps and so on.

Compared to my Pass Zen amp, and especially my 3886 gainclone - this amp has abundance of power reserves - and it plays "neighbor bass" - the bass controll seems so be thigth you dont hear the bass, and theres no distortion, so you dont get a feel of how loud you are playing - but when I go into the kitchen for some coffey, you hear how loud you are playing, and you hear the bass boom....

I think it has a good detail level, but it seems a bit leaned back, the treble is no pronounced - but what I find problematic, is the reproducion of space - my gainclone has it in aboundance - the soundstage is not only between my speakers, it is also on the sides of them - and the music and details seems to "live longer" and not die out so quickly as i ecperience with the ICEpower. Ok - mabye its because the gainclone is bright and treble focused some migth say - but my Zen4 is rather dark sounding, not focusing on the treble - and it also reproduces the soundstage as beeing large, and the notes kind of hang in the air - this the ICE can't do - it sounds very relaxed, not harsh or anything, and has a good detail level, epsecially in ht midrange, but I feel it lacks someting, as described above.

Beeing a "Class A lover", this knowledge kind of pleases me - theres no need to give up those big, power sucking monsters yet - you can't have it all

mobilest

交易区新帖推荐

原帖由 激光鼠 于 2007-3-1 09:28 发表
好几家公司提供数字功放的解决方案，Jeff用ICEpower的，我看网上的对ICEpower的东西一个评价：
I have a 2x250Watt icepower in my system right now - it has a well build dual mono PSU, and a special reg ...

是呀～～我最近也在找资料

因为我讶異它的特性～～

KANGSIR

有兴趣,
因为我朋友刚拿下一台Jeff Rowland　的数字功放!

mobilest

像是目前很多投影機使用的DLP 技術，就是用PWM 的方式產生色階。

mobilest

Tact的数位扩大机是直接把数位讯源的PCM（Pulse Code Modulation）讯号先经过一个八倍超取样的数位滤波器，处理过的PCM数位讯号才送入一个叫做Equibit的DSP内，把它转变成PWM（Pulse Width Modulation）的数位讯号，这种PWM数位讯号是一种高度相同、宽度不同的方波讯号，看起来就像声波的疏密结构。事实上，PWM讯号与Bit Stream讯号看起 茯O一样的，所以也有人把Bit Stream数位讯号称为PWM（有关PWM，文後将再提及）。PWM讯号再经过左右声道Equibit输出模组与类比低通滤波线路（把60KHz以上频率滤除），最後藉著这种PWM数位讯号产生非常高速的强力开与关动作去推动喇叭。

到底这强力的开与关数位动作（等於就是0与1的数位讯号）是怎么推动喇叭发声的呢？就像我们用电池来测试喇叭单体，正接振膜就像前推，反接振膜就像後缩。数位扩大机就是把这个电池（Power）正反的动作以非常高速的状态进行，也就是利用PWM数位讯号去驱动一个高速的切换器（Switcher），藉以控制喇叭单体的发声。到底这个切换器速度有多快呢？一秒切换九千八百万次，也就是说它的速度高达98,000,000Hz。至於推动喇叭的能源当然要从电源供应器供应。

mobilest

交易区新帖推荐

多bit系统以垂直方向把波形切割成很多的电压大小变化，而1bit系统则是以水平方向来把波形疏密排列出来，它以疏密排列的宽度（Width）来容纳音乐讯号，所以也有人称这种记录方式为PWM（Pulse Width Modulation）。

到底这波形的疏密有什么意义呢？我们不要忘了，人耳所听到的声波就是疏密波，这也就是为什么1bit系统再生方式比较类似类比方式的原因。

mobilest

低音层次感強　控制性好　也是D的特色

激光鼠

Class-D对电源波动很敏感，有专门的电路针对电源波动进行补偿，谁补偿做得好，谁的声音就好。我在想，如果Class-A也花点精力在电源补偿上，会不会声音也更好呢？

Ep-71

http://jd-bbs.com/viewthread.php?tid=1289992&extra=page%3D1

av 區內話 hi-fi[s:33] [s:14]

激光鼠

原帖由 nadesico 于 2007-2-27 19:37 发表

鼠标怎么冒出来了
这次上海展会咱们组织一个观摩团如何

什么展会？

mobilest

原帖由 Ep-71 于 2007-3-2 20:09 发表
http://jd-bbs.com/viewthread.php?tid=1289992&extra=page%3D1

av 區內話 hi-fi  

跟您那台一樣的模组~~[s:30] [s:30]

科研级旗舰

原帖由 激光鼠 于 2007-3-2 20:11 发表

什么展会？

3月底，上海“现代音响技术”搞的展览[s:97]

mobilest

http://focus.ti.com/docs/prod/folders/print/tpa3107d2.html

Ep-71

原帖由 mobilest 于 2007-3-3 00:03 发表


跟您那台一樣的模组~~  

[s:11] :funk: [s:19] [s:19] [s:19] [s:19]

冷门二世

原帖由 Ep-71 于 2007-3-3 01:21 发表



:funk:     

即系点啊[s:6]