[Rob Darst]

I have a minor but annoying problem in my home office: whenever I turn my window fan on or change its speed, my desktop speakers pop. My PC, speakers, and fan are all plugged into the same breaker circuit (though not the same outlet), as there is only one for the entire room. All of the equipment is already plugged into surge protectors (nothing fancy, just normal ones).


The audio chain is PC > ASUS Xonar DS soundcard > FiiO E9 destop amp > Swan M1080MKII speakers. It makes no difference whether the E9 is in or out of the chain. I had this same problem with the speakers that I had before the Swans. As far as I can tell this problem only affects the speakers; I do not hear the pops on headphones.


A friend suggested a $250 power conditioner (PS Audio Duet), but that's a lot of money to throw at a relatively minor problem. Is there a cheaper fix, besides buying a battery-operated fan?

 

[jzoz01]

I had a similar problem at one point. Any motor load turning on or off caused the same issue. Turned out to be a loose neutral down in the panel. I'd start there. $250 surge protector isn't going to help.

 

[ljo000]

I think you should call an electrician but otherwise, the monoprice UPS for $180 would also fix the problem.

 

[DonH50]

It could just be the switch arcing (a normal event) and RFI is causing the pops. The usual solution is a cap across the switch, but you have to be comfortable taking apart the fan and soldering the cap(s) in place.

 

[FOH]



Quote:
Originally Posted by jzoz01 /forum/post/20833471


I had a similar problem at one point. Any motor load turning on or off caused the same issue. Turned out to be a loose neutral down in the panel. I'd start there. $250 surge protector isn't going to help.

jzoz, I'm glad your panel-board problem was fixed, but I wouldn't generally associate a loose neutral with this scenario. No offense, but I'd not start there. This is a relatively common issue with both pieces; the fan, and the PC. A PC rig/speakers can easily amplify, or throughput a "pop" like you're hearing. A PC based system is so less sophisticated, and likely whatever amplification stage exists isn't robust and isolated enough to prevent this like a full size rig would be.


A fan, or any motor load can possess a highly inductive characteristic. So when the contacts change state, the emf/counter emf can cause arcing across the gap,..subsequently generating the pop.


If you don't have a decent UPS, I'd start there. You need one on the PC anyway, so if it doesn't entirely eliminate the issue,...at least you've got a UPS for your PC

I'd also check plug orientation, polarity,..etc, with a plug checker/tester, of both the fan, and the PC receptacles. You want to assure the hot is on the appropriate terminal of the device.


If all this fails to work, the switch on the fan may need replacing from excessive arcing.


Be careful

 

[Rob Darst]

Many thanks for the input, folks. I do not have a UPS, and you're right, I should. Is the Monoprice model mentioned above the best buy? I don't need long-term power backup, just long enough to save my work and shut down.

 

[FOH]

I just bought a couple new ones at Sam's Club. They were around $100-$130, APC. I've got a PC work station on one, and my new Panny plasma on the other. The small APC "brick" style are total junk in my experience, stay away. Cool thing about Sam's (Costco too), you know it's a good price without price shopping.


Good luck

 

[ljo000]

Disclaimer: I haven't used the monoprice one and you could probably get something cheaper. It does have very good reviews though, is rack mountable and the specs look good.

 

[DonH50]

I would bet that, although a worthwhile investment, the UPS will not solve the popping...

 

[Rob Darst]

Well, I'll pick up a UPS anyway, it can't hurt. I've noticed the phenomenon in the master bedroom, too, where the fan (a different model entirely) sometimes causes clicking over the TV or clock radio when turned on or up. Crummy wiring, I guess.

 

[DonH50]

No, bad, or at least arcing, switches. Better ones include a capacitor across the contacts to limit such noise by controlling (suppressing) the inevitable arcs.

 

[Rob Darst]

That's reassuring. I'd rather replace a cheapo fan than a cheapo whole-house wiring job! A battery-operated "camping" fan is already on its way.