Taperssection.com

Gear / Technical Help => Playback Forum => Home Theatre & HDTV => Topic started by: justink on November 02, 2007, 04:29:14 PM

Title: Subwoofer problems... help?
Post by: justink on November 02, 2007, 04:29:14 PM
decided to watch a movie last night since i haven't set up the cable at my new place yet...

my sub is connected to the receiver by a mono rca jack.  when i turn the sub on, i get a low constant rumbling, regardless of what is actually going on w/ the sound. 

i unplugged the power, turned on/off, switched out rca cables and the problem is persistent.  if i leave the rca plugged into the sub and remove the other end the rumbling continues when i hold the bare cable on my skin.

this system is about 6 years old but i have had NO problems w/ it before the move.

any ideas?

-j
Title: Re: Subwoofer problems... help?
Post by: Evil Taper on November 02, 2007, 04:46:28 PM
sounds like a ground loop, just plug a ground lift into the socket.
Title: Re: Subwoofer problems... help?
Post by: phanophish on November 05, 2007, 02:13:18 PM
Yep make sure you have a good ground.
Title: Re: Subwoofer problems... help?
Post by: jhirte on November 12, 2007, 11:30:45 AM
I had this issue when I got my DIY sub up and running. After checking the cable TV coax, that was my source. I hit rat shack and got those inline transformers (75ohm -> 300ohm converter?) and that solved it. about 10 bucks in parts, but worth their weight in gold!
Title: Re: Subwoofer problems... help?
Post by: cheshirecat on November 13, 2007, 02:41:41 PM
1st make sure that everything is plugged into the same circuit/recepticle so you know it is all grounding to the same point in the house.  If you still have hum, try disconnecting your TV cable, if the hum goes away then, get a 75ohm isolation transfromer (i picked up a jensen model from markertek and all was good after that).
Title: Re: Subwoofer problems... help?
Post by: pjdavep on November 14, 2007, 01:40:35 PM

I had this happen to one of my Sunfire subwoofers after moved into my house.  The sub somehow went bad from moving it and I had to send it back to the factory for repair.   Hopefully it's just a ground loop issue that others eluded to.

I've had to send three different Sunfire subs in for repair over the last five years and will not be buying one of their subs again.  They seem to last about 5-8 years before needing a rebuild.

Later,
  pjdavep