|
发表于 2004-5-6 20:19:44
|
显示全部楼层
103db/40 ohm 与101db/48 ohm 的分别实际极微,相信分别不大,A900应和A1000 同样容易推动。这里应说明、我其实没听过A900 ,我对它的认识都是来自其他使用者的心得。
英美的耳机爱好者,因为听说A1000 会因过度扩张、导致承轴破裂的可能,又有试用者说分不出两者的声音分别。因此、纷纷改买A900 。因此,需然我是A1000 的使用者,并且对A1000 非常满意。但是我还是会因上述原故,建议买A900 (况且A900比A1000便宜很多)。
至於DT880 我打算买下来,它也是我喜欢的耳机。
但我是在录音室里试听的,感觉是它对系统会有一定要求,要完全驾驭它需要有一定质素的音响器材和耳放才好。
反正论坛上使用DT880 的朋友也不少,你的问题由他们答好了。
《转贴》
high impedance (高阻抗) headphone like "Voltage" rather than "Current". And low impedance headphone like "Current" rather than "Voltage".
For example, we are driving a 32-ohm headphone and producing 1mW, the current we need is:
I = squareroot(P/Z) , where P is the power, I is the current and Z is the impedance.
I = squareroot(1mW/32ohm) = 5.56mA
and the voltage required,
V = I * Z
V = 5.56mA * 32ohm = 0.18V
on the other hand, when we are driving a 300-ohm headphone,
I = squareroot(1mW/300ohm) = 1.8mA
and the voltage required,
V = I * Z
V= 1.8mA * 300ohm = 0.55V
Apart from the impedance of the headphone, another factor which will affect the output level is "Sensitivity", usually stated in:
xx dB/mW.
Here is some good reading regarding impedance and power requirement of headphones:
A Quick Guide To Headphones
http://headwize2.powerpill.org/articles/hguide_art.htm
Understanding Headphone Power Requirements
http://headwize2.powerpill.org/tech/dbohn1_tech.htm
A Class A headphone amp
http://mdlover.dyndns.org/info/class-a-headphoneamp.pdf
there is a detail explanation of headphones' power and impedance relationship in the last document.
cheers |
|