satan_lea 在 2007-4-4 17:06:16 发表的内容 腩兄,再要一对平衡输出转RCA输出的转接头,要NEUTRIK的。请报价。和之前要的声卡线、平衡数码线一起过过来吧。 |
不推荐平衡转RCA
平衡输出类型不同接法不一样,而且一般平衡输出电平比较高,如果高过功放RCA承载电平还有过载的可能。
请参阅:
In wiring a balanced signal source to an unbalanced input, knowing your exact type of balanced output is important. Your equipment’s documentation or its supplier should be able provide the answer.
Balanced outputs come in different flavours; On the one hand there are the true balanced transformer outputs which are completely galvanically isolated and therefore are the least problematic. On the other hand there are the so-called “transformerless” - also named “electronically balanced” - outputs which nowadays are common on most professional equipment. These transformerless/electronically balanced outputs come in two types:
Quite commonly seen is the plain “pseudo balanced” phase/antiphase output, where the equipment’s internal unbalanced signal is simply fed to signal + out (XLR pin 2) by means of an opamp buffer and is fed to signal – out (XLR pin 3) simply by means of a polarity inverting opamp. This doesn’t implement a true balanced output and rather can be looked upon as a pair of unbalanced outputs, one being polarity inverted. Here the above Fig. 1’s wiring configuration is recommended.
Much more sophisticated is the so-called “cross coupled output stage” in which two cross coupled opamps mimic an output transformer. Here the above Fig. 2’s wiring configuration is recommended