Synthesis and generated signals of the air do not use coal, until it from the loudspeaker released from the air only needed the help, but We have enough good reasons not always do so directly.

• 而合成器产生电信号的过程不需要用空气来做煤质，直到它从喇叭里放出来时才需要空气的帮助，但是，我们有足够充分的理由不总是这样直接去做。