cancel
Showing results for 
Search instead for 
Did you mean: 

Speaker Hum :(

rongtw
Seasoned Hero
Posts: 6,452
Thanks: 1,208
Fixes: 11
Registered: 01-12-2010

Speaker Hum :(

when i have my speakers on standby 5.1 microlab FC730 , i get a constant HUMMM  Undecided
had the same with the old Logitech set , so all i presume is it some interference from my mains  .
is there some way of removing this as the hum is annoying  Sad
Asus ROG Hero Vii Z97 , Intel i5 4690k ,ROG Asus Strix 1070,
samsung 850evo 250gig , WD black 2 TB . Asus Phoebus sound ,
16 gig Avexir ram 2400 , water cooling Corsair H100i gtx ,
Corsair 750HXI Psu , Phanteks Enthoo pro case .
21 REPLIES
Moderator
Moderator
Posts: 25,867
Thanks: 1,185
Fixes: 49
Registered: 14-04-2007

Re: Speaker Hum :(

I have a Logitech 5.1 speaker set that has developed a mains hum and I'm assuming a component has failed in its power supply.
It's therefore consigned to the skip.
Does it hum when nothing is plugged into its input socket?

Customer and Forum Moderator.

Community Veteran
Posts: 3,380
Thanks: 2
Registered: 18-01-2013

Re: Speaker Hum :(

Move the speakers to another room and plug in away from any other electrical stuff.
If the noise stops then you might just need to relocate the speakers.
If the hum continues, plug them into a personal stereo player etc without the unit playing - if it still hums then there is possibly a faulty smoothing capacitor in the power supply stages of the speakers. If the hum stops then you might find a 10k resistor from each input to ground will cure the problem.
Community Veteran
Posts: 14,012
Thanks: 539
Fixes: 9
Registered: 01-08-2007

Re: Speaker Hum :(

I have a 5.1 surround sound that someone gave me on freecycle. It was advertised as having a bad humming sound.
Having had tons of dodgy electricals over the years and 'making do' I applied and luckily got it. I got it home and plugged it in and yeah.. it was humming alright... pretty badly so actually. There was no way you could put up with it.
Not being afraid to use a screwdriver I took the thing apart. The cause was immediately obvious - an electrolytic capacitor had gone bad. We don't have a Maplin nearby so I went to the local TV repair shop and gave him a couple of quid for a replacement. Soldered it in and years later it's still working well.
People always used to say things like its a 'bad earth' and stuff like that (what that really meant was a duff connection) but electrical equipment thats working properly shouldn't do that. Solder doesn't just become intermittent unless it's a dry joint and thats rare for manufactured stuff. The chinese are known for manufacturing duff capacitors as they stole an incomplete formula many years ago. So bad is the problem that there is even a website for it - badcaps.net
I need a new signature... i'm bored of the old one!
Community Veteran
Posts: 17,011
Thanks: 1,209
Fixes: 13
Registered: 06-11-2007

Re: Speaker Hum :(

Perhaps they hum, because they don`t know the words  Roll eyes
/:coat  Cheesy
rongtw
Seasoned Hero
Posts: 6,452
Thanks: 1,208
Fixes: 11
Registered: 01-12-2010

Re: Speaker Hum :(

LOL shutter  Grin
they do hum when they are plugged in alone every  thing else off , and when plugged in to another socket .
they are only 2 months old , they have a separate AMP , am sure that its due to the house main circuit  , there must be some way to isolate the socket ?
Asus ROG Hero Vii Z97 , Intel i5 4690k ,ROG Asus Strix 1070,
samsung 850evo 250gig , WD black 2 TB . Asus Phoebus sound ,
16 gig Avexir ram 2400 , water cooling Corsair H100i gtx ,
Corsair 750HXI Psu , Phanteks Enthoo pro case .
Community Veteran
Posts: 14,012
Thanks: 539
Fixes: 9
Registered: 01-08-2007

Re: Speaker Hum :(

More likely that they have some duff chinese capactors in them.
On a similar note I use one of these as my sound for the PC:

Despite being great with MP3 players etc, it picks up the graphics chip in my PC operating and outputs a buzzing/ crackling sound at the slightest change on the screen - everything from a mouse moving to scrolling a page.
I need a new signature... i'm bored of the old one!
Community Veteran
Posts: 17,011
Thanks: 1,209
Fixes: 13
Registered: 06-11-2007

Re: Speaker Hum :(

Old fashioned valve amplifiers, and valve amplifying circuits in radios, used to suffer from "mains hum", which was due to using incorrect values of "de-coupling" capacitors... or the breakdown of de-coupling capacitors... on the power supply rail, and the valve heater rail....
I don`t know how modern "chip" circuitry deals with that problem...
I doubt that Isolating the mains lead/plug will do the trick. 
VileReynard
Seasoned Pro
Posts: 10,645
Thanks: 204
Fixes: 9
Registered: 01-09-2007

Re: Speaker Hum :(

rongtw
Seasoned Hero
Posts: 6,452
Thanks: 1,208
Fixes: 11
Registered: 01-12-2010

Re: Speaker Hum :(

vilefox  Wink that sounds like the problem ,
so what is the answer to stop it ?
maybe one of these may help , with the help of a bit of google  Wink
http://www.maplin.co.uk/tacima-2m-six-socket-mains-conditioner-plus-rfi-filter-for-home-cinema-and-h...
Asus ROG Hero Vii Z97 , Intel i5 4690k ,ROG Asus Strix 1070,
samsung 850evo 250gig , WD black 2 TB . Asus Phoebus sound ,
16 gig Avexir ram 2400 , water cooling Corsair H100i gtx ,
Corsair 750HXI Psu , Phanteks Enthoo pro case .
Community Veteran
Posts: 3,380
Thanks: 2
Registered: 18-01-2013

Re: Speaker Hum :(

Or you could try what I suggested above, relocate it, plug it into a *portable* personal stereo type device and see if the hum stops.
If it doesn't then it is unlikely to be an earth loop.
Community Veteran
Posts: 5,472
Thanks: 288
Fixes: 4
Registered: 11-08-2007

Re: Speaker Hum :(

Most speaker systems use external wall-plug or power 'brick' type power supplies.
Could you find (borrow) another power supply with similar voltage and connector size, and temporarily see whether the hum disappears
A few months ago, my 'Creative' speakers started humming, I borrowed the PSU from one of my wireless access points to prove that it was indeed the original power supply that needed replacing.  Having identified the problem the replacement PSU only cost about £4 on eBay.
Smiley
Community Veteran
Posts: 17,011
Thanks: 1,209
Fixes: 13
Registered: 06-11-2007

Re: Speaker Hum :(

With the above in mind.... I am minded to refer you to my previous statement in the house !...

Quote from: shutter

I doubt that Isolating the mains lead/plug will do the trick. 

So save your money, don`t get a Maplin extension lead ...... yet !
rongtw
Seasoned Hero
Posts: 6,452
Thanks: 1,208
Fixes: 11
Registered: 01-12-2010

Re: Speaker Hum :(

i have tried connecting to a different source , its still there  Embarrassed
the Power supply is direct into the amplifier not via a transformer sorry purleigh
my system http://www.microlab.cn/product_detail.asp?id=223&bigclassid=15&smallclassid=63
Asus ROG Hero Vii Z97 , Intel i5 4690k ,ROG Asus Strix 1070,
samsung 850evo 250gig , WD black 2 TB . Asus Phoebus sound ,
16 gig Avexir ram 2400 , water cooling Corsair H100i gtx ,
Corsair 750HXI Psu , Phanteks Enthoo pro case .
VileReynard
Seasoned Pro
Posts: 10,645
Thanks: 204
Fixes: 9
Registered: 01-09-2007

Re: Speaker Hum :(