Power Supply Whine, Need Audiophile Help


Ok posting this problem on an audiophile board... because you guys seems far more knowledgable regarding things like this.

The problem is with the 37ish PC power supplies i plug into my wall. ive tried every socket in my apartment. immediatly when the power supply are plugged into my wall (no computer components attached), they emit a high pitched whine. whine increases in volume once the power supply is flipped on the On "I" position.

Im not positive, but I think the whine is coming from the transformers. This whine is not normal.. and theres no way all 37 PSU's could be defective.

My question for you guys is... could poor wiring.. bad sockets, whatever... cause this?? Will a power conditioner solve this? What can I buy.. for a reasonable price.. that will send clean, constant powre to my electrical components.

Id appreciate any and all help.
thank you
128x128dwgingrich
you are describing completely normal behavior for a switching power supply; there's no way to prevent it & they all do it
Actually you could have DC current from a outside line transformer that creates the whine. Some sort of average voltmeter will alow you to detect this. If not, call your local power provider and have them check for DC current in your house. This is a common problem with transformers that buzz
Actually, Bob was quite correct in his response. ALL computer (read "switch-mode") power supplies have some degree of high-frequency whine. Read up on the design priciples behind SMPS and you'll discover why they make that awful high-frequncy whining.

Without being too curious as to why you have 37 PC power supplies plugged into the wall at once, might I suggest that a little quick math is in order to calculate the cumlative amperage draw on the circuit(s) in question. It sounds like you have all these power supplies plugged into one giant power strip fed from one, two or four outlets. If such is the case, you could well be drawing peak current of over 55 amps (considering an average power supply draw of 1.5 amps per unit...could be more, could be less). That's a lot of juice. You mention "apartment". Most are fed from no more than 4 15-amp circuit breakers. Might I suggest that even with no load on the power supplies, you are still drawing a lot of current, even at idle. Your apartment's power system wasn't designed to be used as a server center, anymore than it was designed to be used for industrial arc welding.

The other item of concern also revolves around the design of SMPS, and the amount of back-EMF generated by them. They spew tons of garbage back into the power line. The more backwash of EMF, and more noise all those SMPS are likely to make. By having so many of them plugged into a circuit clearly not designed for such use, you are, in effect, compounding your own problem (and contaminating probably everyone in the building (on that feeder branch)). Glad I don't live in your building. Hope this helps.

-Richard