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请教madog兄,请重起兄帮忙翻译:关电声系统的q值问题? [复制链接]

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1#

Good work buddy, thanks.
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2#

KENTRYFO 在 2004-2-27 20:34:52 发表的内容
还没完!一下是摘抄的一段比较经典音响q值的论述。估计跟madog兄的观点会比较一致。

    正像在敲击钟时会产生某一音调的声音那样,装于音箱内的低音发音单元也自会在某一频率上产生谐振。此一谐振的特征便是音箱的一个重要特征,将会对重放出的音乐产生重大的影响。品质因素Q便是用来表征低音单元在箱内的谐振情况的。
    具体地讲,音箱的Q值等于谐振的中心频率峰值除以峰值的带宽。在很窄的频带内谐振的低音单元的Q值便比在宽些的频带内谐振的低音单元的Q值要高些。谐振越为尖锐,’续Q值便越高。
    低音单元皆有其自身的谐振Q值,并经音箱的Q值作些修正。这些谐振在合并在一起并相互作用后,便会形成系统的Q值。通常,系统的Q值在0.7到1.5之间.将Q值小于1的情况称为过阻尼(overdamped) ;而将Q值大于1的情况称为欠阻尼(underdamped) o在评价音箱时,有时人们会用“阻尼的低音”这样的说法。意思是,低音虽然较为丰富和温暖,但却不够紧凑厚实。从技术上讲,这些评价术语说的都是音箱系统在消声室的响应(anechoic response),即音箱在一间没有反射的房间内的响应,即在谐振频率上是有所抬高还是有所降低。音箱系统Q值为0.5时的临界阻尼便会有最好的瞬态响应,而且还不会有听得出的拖尾,也即在所加的音频信号中止后,低音单元便应立即停止移动。Q值越高,低音单元的振动便越多。
    客观上看,欠阻尼的方式虽然可以获得更多些的低音,但低音却不太紧凑厚实,没有确切的音调,易于出现“单音调”的低音。过阻尼的方式虽然能够产生非常紧凑厚实和干净的低音,但却会有相当清瘦的低频响应。过阻尼的音箱虽然低音稍许少了些,但低音的音质却比欠阻尼的音箱要好。过阻尼的音箱能够更好地分辨低音的细节,但低音往往缺乏力度和震撼的气势。大多数的音箱设计师皆将Q值等于0.7作为设计的目标,以便能够在低频响应
延伸较宽(仅比谐振时低3dB)和较好的瞬态响应(只有很小的拖尾)之间进行折衷。但是,也有些设计师坚持Q值为0.5才是理想值。并认为在Q值高于此值时,低音的音质就会变差。成批制作的普及型音箱大体上都是按照高Q值的欠阻尼方式设计的,从而以其听来相当震撼的低音来招睐那些不大懂行的顾客。比如宣传广播车所播放出的那种低音,虽然低音很响,很有冲击感,但却分不清音调,也缺乏动态的细微之处,没有丝毫音乐的细节。人们
听到的那些轰隆声只不过是低音扬声器在音箱某一特定频率上的谐振,同所希望有的真正High-End音箱所发出的那种纯正之声还有着天渊之别。

但是,现在,我要提出我的观点:对于空间的Q值,并不能完全引用音箱Q值的概念,因为我们就处身室内!存在着直达声和谐振声在听感上的本质区别!我以为:就听感来讲:听音空间的Q值不妨设于稍高的过阻尼状态,关键是最终的低音还是要真正由音箱发出来才作数!而因稍高Q值的过阻尼状态产生的响应,则有利于参生环境铺陈的效果,起到类似“风雨雷电听音响”(见:http://www.hifi168.com/Bbs/article.asp?titleid=36082&ntypeid=10)中的效果。



Good work Kentrfo, yes it is very close and it comliment to what I wrote in
particular, the last paragraph, bass is coming out from the speaker.

But let me add one more, the bass is coming out from the speakers but at
the end , the bass performance is based on the amplification system
including the source (in this case CD player).
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3#

KENTRYFO 在 2004-2-29 16:17:50 发表的内容
是的,MADOG兄,原来我用88C推我的音箱系统,的确发挥、控制不了CD的低音,所以原来我并不喜欢听这个碟片,因为它(在没有低频铺垫的情况下)真的在我的系统中不成其为音乐了,加上了风声、雷声、雨声后,才有了音乐的感觉。现在,我用改进过的99C推,那确实是完整的音乐——好听、耐听!!从而联想到:不发自音箱的环境铺垫的声音也是有其存在价值的——对于CD20HZ-20KHZ的限制标准及一些录音没有把低频泛音充分反映出来 来说,故有此说。目的就是补充标准外和系统播音能力的声频缺陷!反过来,能不能承认20KHZ外的高音同样也有同样存在意义?!——低音用环境声达成,高音用过耗的“多余的”信号达成?!!——共同形成气氛的铺垫!!
    ——好悲哀的CD电声系统!!太不完美了。
    表演现场的气氛出不来,需要重播现场的气氛来补充!!!!重播永远是再创造的过程!!!!!!!!!!



Absolutely agree except I would think CD is a rather mature sound source.
Take a good CD player as an example. CD sound has something that the
LP can never be the same. That is the timber of every instruments and
vocal coming from a good CD player, it has more muscle while the LP
is on the other hand rather slim.

Some folk like slim ladies, some folks like strong built woman. Which one
would you prefer?

I would like the latter kind.

But LP is not all that bad in terms of musicality, I like it soft and musical and
lots of air comig out with ease. Puch ? sorry to say, seems a bit difficult.

If you are expecting LP would become more punch and solid musicle,
then you have to use heavy duty turntable, tone arm, and cartridges with
stylus pressure of at least 3 gram that more audiophiles cannot accept
this except the pros. Besides, LP with good muscle is hard to find those
golden days not to mention now.

I believe CD is better than LP now in terms of varieties.
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4#

重起 在 2004-2-23 15:41:39 发表的内容
In your case KENTRYFO, the Q is to be adjusted to suite the room mode.
以KENTRYFO兄的情形看来,Q值应按你房间的模式来作适当调校。

In a simple saying, lower Q, fatter bass and has a broader bandwidth. Higher Q means there'll be likely to have a peaky bass
depends on tune frequency that give an impression of clean
and fast bass
简单地讲,Q值越低,低音越肥大同时频宽也越宽。更高的Q值意味着很可能会有一个隆起的低频视乎音调的频"lui"(不会拼)可能会赵成一个干净,快速的低音的假象。

In electronics including all EQs, speakers, or even the high
frequency device such as transmitter, Q factor of 0.7 is the
most balanced Q factor.
在电子设备中,包括所有的均衡器,音箱甚至高频的设备例如发射器,0.7的Q值是最平衡的Q值。

For example of speakers, a normal speaker (such as subwoofer)
will be tuned to a Q factor of 0.7.
以音箱为例,一个普通的音箱(如超低音音箱)就会将Q值调到0.7。

If you wanted more punchy bass like in the car sub or home
theatre then the Q factor may reach up to 0.9 or 1.
如果你想要像汽车用的或家庭影院的那种冲击力强的低音,可把Q值设高到0.9 或1。

The higher the Q, the bass band will become peaker and the
Q facor of 0.7 is flat and balance.
Q值越高,低频带的峰值越厉害(突起),而0.7的Q值(低频带)是较平和平衡的。



Very good interpretation.
Yes only those like more excited sound performance would like an
average Q factor.

I think Graphone is not the only company have this concept. There is
Vegen who recently introduce the Xcalibur are designed with the similar
idea.

The Xcalibur is a system of an integrated amplifier and one active
subwoofer and one pair of bookshelf. There is matching CD player.

The whole idea is, through the adjustment of the subwoofer, one can tune
to match to the room mood.

The Xcalibur even further to cope with different recording, from old
analogue recording to the latest digital recording.

I heard once, very impressive but have to match with good cables and
interconnects.

I may say this Xcalibur is sort of all round audio system that be happy to
almost every kind of music and recording and user friendly.

User adjustment mainly based on the tuning of the subwoofer and it's
amazing.
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5#

In your case KENTRYFO, the Q is to be adjusted to suite the room mode.

In a simple saying, lower Q, fatter bass and has a broader bandwidth. Higher Q means there'll be likely to have a peaky bass
depends on tune frequency that give an impression of clean
and fast bass

In electronics including all EQs, speakers, or even the high
frequency device such as transmitter, Q factor of 0.7 is the
most balanced Q factor.

For example of speakers, a normal speaker (such as subwoofer)
will be tuned to a Q factor of 0.7.

If you wanted more punchy bass like in the car sub or home
theatre then the Q factor may reach up to 0.9 or 1.

The higher the Q, the bass band will become peaker and the
Q facor of 0.7 is flat and balance.
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