More commonly the switching frequency is up in the tens of kHz with some sub-harmonics extending into the audio band, plus possibly also some low-frequency ripple. Then there are the really cheap switchers, with a switching frequency right in the middle of the audio band.
上述這段話有提到some sub-harmonics會延伸到audio band, 看起來應該是專業人士說的, 畢竟頻率並非方波而它的確會跨到不同頻帶造成干擾, 如果您對EMI測試不陌生的話很容易可以聯想到, 這也就是為何switching power不是最佳用在audio機器上的主因, 音響機器內的確幾乎很少用 switching power的, 應該說幾乎看不到.
電腦內供電過於複雜, 有cpu, MB, BD ROM, HDD, SSD, ...故switching power是最適合的可同時供應不同電源且有能力在短時間提供大電流的power supply, 唯對聲音最大殺手switching power也脫離不了關係, 故若要有較佳聲音且不放棄switching power的話就是要減少系統內過於頻繁的變動以減少干擾的反應.
引用:
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作者Eav
http://tangentsoft.net/audio/opamp-ps.html
人耳最多聽到2KHz，隨年齡遞減，這是常識吧。
業界人士又如何？到底想說啥？交換式電源供應器一定不能用於音響嗎？
The disadvantages of a switcher are that the switching component adds quite a bit of noise to the output power. I’ve seen many different switching frequency signatures. The better switchers have all of their noise up in the megahertz range, so that there’s virtually no noise in the audio band. More commonly the switching frequency is up in the tens of kHz with some sub-harmonics extending into the audio band, plus possibly also some low-frequency ripple. Then there are the really cheap switchers, with a switching frequency right in the middle of the audio band.
這篇是講交換式電源用...
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