Subwoofer Loud Hum

[esb71]

Help… About a week ago, my subwoofer started to make a loud hum when the system was powered on to watch TV. The hum is extremely loud and vibrates the room and the only way to stop it is to turn the volume down on the back of the sub or disconnect it all together! I can turn the volume up or reconnect after a few seconds and everything is fine. This is extremely annoying.

I have tried changing the outlet the sub is hooked up too, I’ve bought a new double shielded cable and I’ve even tried a 3 prong to 2 prong plug adapter, even though my sub is a 2 prong style.

Does anybody have any idea of what’s wrong? I just want to figure out if it’s the sub or the receiver that is not working right and which one needs to be replaced… I’m trying to keep from purchasing both.

Here’s My Setup:
A/V Receiver – Sony STR-DE825
DVD Player – Sony
VCR – Sony
Speakers – Energy Take 5 (Classic)
Subwoofer – Energy XL-S8 (100W)
SAT/DVR – DirecTV TiVo
Wii Game Console
iPod

 

[MinusTheBear]

Help… About a week ago, my subwoofer started to make a loud hum when the system was powered on to watch TV. The hum is extremely loud and vibrates the room and the only way to stop it is to turn the volume down on the back of the sub or disconnect it all together! I can turn the volume up or reconnect after a few seconds and everything is fine. This is extremely annoying.

I have tried changing the outlet the sub is hooked up too, I’ve bought a new double shielded cable and I’ve even tried a 3 prong to 2 prong plug adapter, even though my sub is a 2 prong style.

Does anybody have any idea of what’s wrong? I just want to figure out if it’s the sub or the receiver that is not working right and which one needs to be replaced… I’m trying to keep from purchasing both.

Here’s My Setup:
A/V Receiver – Sony STR-DE825
DVD Player – Sony
VCR – Sony
Speakers – Energy Take 5 (Classic)
Subwoofer – Energy XL-S8 (100W)
SAT/DVR – DirecTV TiVo
Wii Game Console
iPod

Have you added anything to your system lately like a cable box or any other equipment. If your subwoofer was working fine before and you have not installed anything else into your system and now you are experiencing a hum possibly your amp on the subwoofer could be going.

 

[esb71]

The only thing I've added in th past few months was the Wii. I did change the setup confuguration a while back. I used to have all of the video going direct to the TV, now I have it all going into the receiver, using the monitor out to the TV. So do you think it's the sub?

 

[croseiv]

Do you have your sub's cable plugged into the correct jacks?

 

[esb71]

Yes, it's pug into the sub "Line In" on the back of the sub and there's only one sub out on the receiver. The back of the sub does have another input, labeled "Xevor" (i think, I'm not in front of it now..

 

[TLS Guy]

Help… About a week ago, my subwoofer started to make a loud hum when the system was powered on to watch TV. The hum is extremely loud and vibrates the room and the only way to stop it is to turn the volume down on the back of the sub or disconnect it all together! I can turn the volume up or reconnect after a few seconds and everything is fine. This is extremely annoying.

I have tried changing the outlet the sub is hooked up too, I’ve bought a new double shielded cable and I’ve even tried a 3 prong to 2 prong plug adapter, even though my sub is a 2 prong style.

Does anybody have any idea of what’s wrong? I just want to figure out if it’s the sub or the receiver that is not working right and which one needs to be replaced… I’m trying to keep from purchasing both.

Here’s My Setup:
A/V Receiver – Sony STR-DE825
DVD Player – Sony
VCR – Sony
Speakers – Energy Take 5 (Classic)
Subwoofer – Energy XL-S8 (100W)
SAT/DVR – DirecTV TiVo
Wii Game Console
iPod

If your sub is two prong, I doubt this is a ground loop. It would be most unusual for a receiver to cause this problem. It sounds as if you have a ground intermittently breaking. I wonder if it is the the ground to the line input connector to the sub. Try wiggling this connector and see if it induces the problem, or stops it when the hum starts. I suspect a break in a circuit board ground plane some place. When this occurs it is at the connector more often than not. Also try wiggling the LFE out connector on the receiver.

The other possibility is a failed regulator or diode in the power supply of the sub, which resets after powering down.

 

[esb71]

I have already powered down the sub and unconnected everything and reconnected. But I will try and wiggle the connections next time I power up the system. Thanks for the tips.

 

[MinusTheBear]

Try disconnecting the subwoofer from your system entirely and take the subwoofer and plug it into an outlet in another room in your house. Do not connect it to any equipment and turn it on and off a couple of times and see if the hum still persists.

 

[Midcow2]

A think there is a floating ground on your AVR

The only thing I've added in th past few months was the Wii. I did change the setup confuguration a while back. I used to have all of the video going direct to the TV, now I have it all going into the receiver, using the monitor out to the TV. So do you think it's the sub?

.

I don't think it is the Wii

A couple things to try to isolate the problem:

(1) Try switching your video back directly to the TV and see if the problem goes away.

(2) Make sure all of your equipment is grounded. If you have a ungrounded or floating ground equipment and you connect it to the AVR the video could be acting like a feed-back antenna.

(3) Try disconencting and then connecting source back one at a time. Does it happen with all equipments sources on only one.


Good luck!

P.S.- you weren't by anychace watching the "Bees" at a loud volume

 

[esb71]

Thanks for all of the advice... but it's fixed now. I powered down the sub, unhooked it's connections at both ends. When I hooked it back up, I used the other Sub Line out on my receiver, since I only have one sub. I turned the sytem on and everything is working fine now! So I guess the first Sub Line Out jack is what's not working right, which means the second jack may be next, but atleast I've narrowwed it down to the receiver. I'm guessing a new receiver may be in my future... I'll just have to read some reviews here and get a new receiver if the final sub Line Out fails. Thanks for everybodies help!

 

[TLS Guy]

Thanks for all of the advice... but it's fixed now. I powered down the sub, unhooked it's connections at both ends. When I hooked it back up, I used the other Sub Line out on my receiver, since I only have one sub. I turned the sytem on and everything is working fine now! So I guess the first Sub Line Out jack is what's not working right, which means the second jack may be next, but atleast I've narrowwed it down to the receiver. I'm guessing a new receiver may be in my future... I'll just have to read some reviews here and get a new receiver if the final sub Line Out fails. Thanks for everybodies help!

I strongly suspected something like that. It is not uncommon for board mounted RCA sockets to fracture from the circuit boards. Just make sure you handle the other one with care.

 

[MinusTheBear]

Cool, cool. It is always good when you do not have to spend money to get the problem fixed.

 

[croseiv]

Glad you fixed it!