http://www.amazon.com/gp/product/B004GJXTQS/ref=ox_sc_act_title_5?ie
=UTF8&m=A21Z5WJQSGVB69
http://tinyurl.com/7xo766q
這是amazon 0204 USB音效卡
第一個評論By Reticuli (Las Vegas)提到一段關於應該是阻抗方面的問題
Headphone jack may be Class A circuitry, but is somewhat limited voltage
(i.e. volume, common with Class A) and is inherently loaded to 22 ohms, which
means your headphones need to be over 176 ohms to be driven well (22 ohms X 8
for proper electrical-mechanical damping). I'm still finding it sufficiently
low to drive the 100 ohm ER4S pretty well. The 22 ohms is probably a
necessity for the circuit design so that the headphone jack can perform as a
line out nearly as well as the rear outs do. But this means it's really not
suitable for headphones under 100 ohms, as they will come off sounding
thinner, edgier, and not particularly dynamic as they should.
這款設計的耳機孔適合推超過176阻抗的耳機
阻抗低的耳機接上去反而會推不好
這個原因是什麼??
以前只看過人在討論 耳機阻抗太高 ==> 怕訊源推不動
這個倒是整個反過來 怕耳機阻抗太低 ==> 訊源推不好
是真的有這種逆向理論嗎 ?
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※ 編輯: wpd 來自: 210.61.67.199 (02/08 19:44)
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