Axiom Home Page Forums General Discussion Technical Questions A person I work with is having this problem???

Any thoughts I can give him?

Looking for trouble shooting advice.
I have a Denon A/V receiver. It was on yesterday as I was watching football. At or very close to the time my wife plugged in the vacuum, my speakers started making a continuous popping noise. I unplugged the vacuum and shut down my system. Upon turning my system back on, it seemed fine until my wife ran the vacuum again at which time, I lost the left & right front and center speakers (i.e....they went silent). The back three (left, right and center) are all still working fine. The front three speakers (which are no longer working) are on the same wall as the outlet she was using for the vacuum.
Any thoughts? It seems very strange that the vacuum being plugged in nearby should have any affect on the speakers or receiver, but it is the one common denominator. The outlet she was using is directly below the three speakers.

I have personnally seen a mainframe reboot (something very rare) despite a UPS after a cleaning lady had plugged a vaccum cleaner on the dedicated circuit. My advise is usually to use a broom...

Randy, did the vac look like this? Does he live near you?




Did the guy check the fuses on the Denon?

lmao

I'd probably suggest to him to not have your wife vacuum at the same time that you are trying to watch football at your house.

She should get a new vacuum cleaner, it sounds to me like the vacuum is sending some bad waves over the power lines on the return side of the circuit.

That's just gonna upset her, Eric.

I would get her a dustbuster instead.

How about a feather duster and a French maid outfit?

OK! THAT'S IT RITE THAR!!

As "little Johnny" would say, I like the way you are thinking!

Disclaimer: I don't even pretend to understand home wiring or how it would affect your gear, nor am I an electrician or electrical engineer. So take this with a huge amount of skepticism...

Could there be a voltage problem when the vacuum cleaner is running? Is it a new vacuum? Or does the vacuum need to have its dust bin, bag, or filters changed? Some vacuums pull a lot of amps from the wall. Many are pretty serious power-consumers. And when they get clogged up with dust, I wonder if they pull even more juice as the motor strains?

Could this perhaps cause a voltage drop at the outlet that is then causing your receiver's internals to produce the popping noise? I have no idea how, but digital things can do strange things when not presented with enough power. Who knows, there could be some D/A converter in your Denon that's really sensitive.

All I know is that I have a Belkin PF-60 glorified surge protector. Arguably, its most useful feature is the digital readout of input voltage and output amperage. Other stuff in my home affects the voltage that my HT system experiences. When I vacuum (yes, I vacuum), and plug into the same circuit in my den that the HT is using, the vacuum does affect the voltage on the PF-60. And before the PF-60, every time my neighbor's HVAC system kicked in (our homes' power runs from the same transformer out above the street), or my wife fired up the clothes dryer, it would send a single, fairly quiet but audible *tick* noise through my HT system. So circuit-based electrical noise can make it all the way to the outputs of a speaker.

Well, the user turned off the receiver and unplugged for about 10 minutes, no change. Then I had him reset the microproccesor, and now none of the speakers are working, even after attemting the Denon auto setup, says there is a problem right off the bat.

Hope he has a warranty.

That doesn't sound too promising

UPDATE!!!!!!

what do you guys think?

Continuing my story...

I ended up bringing in my Denon receiver for servicing to American (the place I bought it). I thought they serviced in-house, but actually they have a proprietary repair shop somewhere in Wisconsin they ship to that handles all repairs. Regardless, I was pleased with their response time as I received a call from a technician at their Wisconsin servicing center the day after I dropped it off at American in Johnston. The bad news. He indicated my BSP board was bad and would need to be replaced at a cost around $300.

This is a 3 1/2 year old unit, so I'm not pleased with this news especially given the fact I believe I can buy a comparable new Denon for about $500.

I had the technician look up my servicing record because I'd had a problem with my original unit shortly after buying it. They replaced it due to being under warranty. He indicated the original unit was replaced due to the same issue -- bad/failing BSP board.

My conclusion (and I'd be curious to hear if anyone has other thoughts). The outlet in the main living area that the vacuum was plugged into must share the same circuit (not sure if proper term) as the outlet I have my equipment plugged into in the backroom. For some reason, this must have caused the problem and I'm guessing, was the same thing that caused my original unit to go bad 3 1/2 years ago. That said, I'm a bit surprised the surge protector did not prevent any problems and/or the Denon's own internal protection devices (assuming there is such a thing) did protect it from damage.

At the end of the day, I'm probably going to buy a new A/V receiver and also will need to add a dedicated outlet for my stereo equipment to prevent this in the future. Other thoughts?

I had said it sounded like the vacumm was causing a back feed into the receiver. I am curious as to whether or not his house wiring is newer or older? If newer, the receptacles should be polarized and my theory is not valid but if they are not polarized the plugs could be wired inconsistantly and pulses etc from electrical items could be coming through any surge protection on the wrong side of the plug(neutral) which might not have internal protection on the amp.