Terrible sub hum -- I've tried almost everything. Help!

DarrenAlan · 08-12-2003, 01:26 PM

Own a Paradigm PDR-10 sub. It started humming perhaps 6 months ago, intermittently at first, now all the time and seemingly louder as time goes by. Pretty much unbearable now except when playing music loudly. I've tried:

-Ground loop isolator (didn't work, prevented reception of HDTV channels)
-Isolation transformer (didn't work)
-Unplugging cable input into set-top box (didn't work)
-Unplugging each component one by one (didn't work)

The only things I *haven't* done are unplug ICs from the amp one by one (although I don't see how that would be the problem) and running power to the sub from another circuit (which would be an unpractical solution for everyday living).

I'm wondering if the sub amp itself has gone bad ... in which case it would provide me with the perfect excuse to upgrade to a better, tighter yet inexpensive sub such as the Dayton/Partsexpress kit or the Adire Rava.

Thoughts? Any further suggestions? Thanks in advance.

Mark Kunschke · 08-12-2003, 02:50 PM

Have you tried a cheater plug 3 to 2 prong adapter? I had a hum with my amp and this fixed it. It's not recommended because you lose the ground, but something to try.

DarrenAlan · 08-12-2003, 02:59 PM

My HT system is fairly modest and all plugs are two-prong except for the Monster HTS-2000 that all my equipment is plugged into.

Plus I have a 3-year-old who lurks around equipment from time to time (when I'm not watching, of course) so can't take the risk of floating a ground.

Thanks for your suggestion tho.

toddi · 08-12-2003, 03:05 PM

I had a similar buzzing noise from my sub and it turned out to be the large caps. Replaced all four caps and no more hum at least for the past six months. Might be something to consider.

DarrenAlan · 08-12-2003, 06:16 PM

Thanks. I'm not terribly handy so, while that's probably a relatively easy and cheap fix, it's not one I think I can do myself.

I make Tim Allen look like Bob Vila when it comes to home repair/home improvement projects (although after being a homeowner for a dozen years now, I've gotten better).

**HTF Ads**

Matt_Doug · 08-12-2003, 08:15 PM

Try grounding the chassis of your sub to the ground terminal on your HTS 2000 (if it has one) see if that helps. Unfortunately if it does you have a short somewhere and you'll need to hunt that down.

Paul.Little · 08-12-2003, 08:17 PM

It used to be fine, then it hummed intermittently, now it hums all the time...

Have you considered the possibility that it's just forgotten all of the words?

Sorry, couldn't resist. The progressive nature of the problem strongly suggests there is something wrong with the amplifier. Have the unit serviced.

Or buy a new, more powerful, tighter, better, etc... subwoofer.

Gordon Groff · 08-13-2003, 07:53 AM

I had hum from my sub power amp too. First from an old amp, then from a new Samson S1000. Both times I lifted the ground on the sub power and it went away. I just upgraded to a new Crown K2 and no hum. How weird is that?

FWIW,
Gordon

DarrenAlan · 08-13-2003, 10:50 AM

A couple of questions:

1) How do you lift the ground if it's only a two-pronged plug?

2) I would imagine caps need to be soldered, correct?

I think I'll take Paul's advice and upgrade, perhaps to Adire Rava or, budget permitting, SVS 25-31. Even the wife is on the bandwagon because her hearing is MUCH more sensitive than mine and the hum is driving her batty.

Fortunately, we have an addition above our garage that doubles as a home theater and play room for our little girl, so size and aesthetics aren't a big concern.