Logitech Z-5500 Subwoofer hum noise

douglasw

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Jan 31, 2012
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Iv notice sense i had my Z-5500 theres a slight hum that comes from the subwoofer when its turned off..Iv checked on line and theres lots of reviews about the hum noise that it could be this or that so i stripped it all down and it still makes the noise...Im starting to thing this in normal because it does have a transformer inside and i know transformers make some kind of a hum even the fransformers that are up top of telephone poll to the ones that are in those big green boxes that are along the road but still the topic really gets on alought of peoples minds...so im asking does anyone know if its a problem or thats just they way they are..
 
Solution
Its not a "problem", its a common trait of all inexpensive audio systems. Expensive audio equipment and systems have proper insulation and well designed circuitry to minimize noise.

douglasw

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Its coming from the amp..A slight hum..Some people say its coming from the speakers but mine is hardly noticable but its there..It dont get in the way of performance..Some say its the cable going to the pod so what i did was disconnect everything from the sub and it still hums..Theres no problem living with it but as they say if you have a lil problem you should fix it before it becomes serious...Myself i had a guitar and a speaker once and when i turned it on i remembered it also had a hum so im thinking maybe the sound im hearing is from the transformer thats in the sub...All i can tell you the sound is coming from the black box i sound blondish but thats all i can tell you..
 

douglasw

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Yes iv did alought of reading over this matter and i do say your answer was what i came up with...Logitech only having a 2 prong plug may have a ground problem...i also read you shouldnt have your subwoofer within 2 feet of your Pc & mine was within 2 feet so i moved it today & it did solved my volume jump problem..At low volume it would increase & decrease and by moving my sub it solver that problem...Mind you the hum noise isnt like alought of peoples who complained while beside the sub if you stand up beside it you wont hear the hum..Its only when you get right down on your knees but still if i can solve it ..It will be a bonus...Thanks for the tip man i will check out the ground lift adapter..
 

douglasw

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Yes off as pushing the off botton on the pod..But if you hit the switch on the sub then the hum stops....Iv went to a local electronics store & talked to electrician of 25 years and went over what was happening and he asked questions like is the humm coming from your speaker also which is no..and does the hum fluxuate which is no i told him its a slight hum then he asked is your system running ok and i had to say yes..So he came up with the conclusion you cant fix what not broken so dont worry about it..He told me all it was is low frequency interference and you can drive yourself crazy trying to fix it...So what ill do is i wont worry about it but maybe some day someone will say try this and it will work...Plus id hate to pack it and send it to Logitech and get it back doing the same thing....Anyway thanks man for your concern
 

blackhawk1928

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Yeah, thats what I was thinking. Simple cable interference. However I'm wondering why its happening despite the subwoofer being off. Try unplugging it from the outlet and see what happens. Its likely interference that can be fixed with better insulated cables.
 

douglasw

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What iv tried is strip all cables from the woofer & plug the sub back in & still a hum so wouldnt this eliminate cable interference or maybe you meant inside the sub this is what im starting to think..Only way to stop the hum is hit the switch thats on the sub or just pull the plug from the wall...Im currently waiting for a e-mail from Logitech see what they think. If they come up with somthing ill sure let you know the outcome...thanks
 

douglasw

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I forgot to mention that tech ask me to try plugging the sub into another plugin thats located on a different sircuit in the house no luck.. i cant see that would make a difference because my system is plugged into a UPS battery backup you spend big bucks on a system you need a lil insurance the UPS gives....There one truth to what the Tech said it could drive you crazy trying to figure it out..Anyway i have to admit the system sure does puts out the quality sound so i guess ill but my mind to ease.
 

blackhawk1928

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That sounds what I thought. If the subwoofer is plugged in, it could still have power at standby. If it picks up any interference signal it can cause it. Cellphone, poorly insulated wires, perhaps a busy wifi area. I'm not the biggest expert on interference, but it sounds like it.

It could also be the very circuitry. Inexpensive systems have problems with many times.
 

douglasw

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I was talking to a computer tech of 20 years who's been into computer before windows 95 and the internet came out and what he said the hum is normal we even went to his place and he has a big ass subwoofer connected to his Pc and his had the same hum & he has had his for quite a few years...He asked me the same question as the other tech like does ur speaker give off noise and a few other iv heard before ...so what im going to do is theres a online Canadian site like Ebay its called Kijiji and i found a girl who has the Z-5500 and her volume pod took a dump & her warranty expired so shes selling whats left for $90 bucks so thats a deal i just bring my pod and check it out...Anyways man thanks again for the concern
 

douglasw

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Thanks man thats the best answer iv heard yeat..Iv been e mailing Logitech support back and forth and the last e mail they told me to replace my fuse in the sub...does this make sense anyways i wont contact them anymore...Maybe next they will ask me to stand on my head or somthing...anyway when the time comes to pick my best answer youll be picked.... thanks again..
 

jerjerrod

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I have had FIVE sets of z5500s since I bought the first set 6 years ago. One set went bad, returned it, for replacement. Then after the warranty ran out, I unfortunately bought a new set, and that one went, then another, then another then Logitech had to refund my money for the lemon clause. I got all my money back, but still have the old set that had gone bad after the warranty ran out. I wondered if there had ever been a fix found for the low humming noises from both the bass and the speakers. (All 5 sets had the exact same problem in them) The middle stopped completely, the rears and the fronts had a low humming noise as well. The sloburn fuse never went bad and is still intact. It would be nice to get them to work again. They are GREAT speakers, when they work. Not a good thing to say about speakers at all. So, it is not the fuse. I think it may be the control pod though. Mine is a R526 so I would need a R636 or lower to replace it with. I am not sure why though. Why aren't they all the same anyway? Of course, why can't Logitech make speakers that don't have the same issues the entire time they had been on the market? $400 for speakers and these issues NEVER went away. Nice.

And BTW, I have a set of Monsoon(!) 5.1 speakers that are about 12, TWELVE, years old that still work fine and are hooked up right now and working like a champ. Guess I should have never ever bought the Logitech's in the first place.