Dayton SA240 Subwoofer Amplifier Hum problem

[trinnylax123]

Well I remember buying this amp almost 3 years ago and it had a bad hum when plugged into the preout on the amp, so I switched outlets in my apartment and it worked just fine (for the last 3 years). Now I moved to a new a apartment and the hum is back. I'm assuming it's a ground loop problem, I just am not sure how to get rid of it.

I read the reviews on the amp and many other people mentioned the same hum. One guy mentioned "adapter from Walmart and removed the ground lug on that and plugged the amp into it, and the noise vanished." Except I'm not exactly sure what adapter he is talking about. I tried like a ~$50 power strip that said it removed ground loops to no avail. And I'm assuming that 3 years ago I switched the subwoofer to an outlet with no ground (very old house).

Any ideas on what adapter I should buy for the outlet, and how to remove the ground "lug" to get an ungrounded source for the subwoofer?

I tried hooking the woofer up through the cables for the L/R mains and it worked fine with no hum, but I'd really prefer the preout so I can move it to another spot in the room without cables from the mains running over to it.

Thanks for all the help!

[daryl]

Before you probably found an outlet with a similar ground signal to what the rest of your system was plugged into.

When the ground signals at different interconnected componets differ you have a ground loop.

The best thing to do is locate your reciever and subwoofer very close to each other and use a short interconnect for the signal and plug them both into the same outlet with short cords.

No unbalanced componet should be grounded since they cannot reject ground loops.

I'm guessing these plate amps are being required by law to have grounds for some special reason because other unbalanced componets do not have grounded plugs.

The ground connection might be the problem.

Any componet with a ground connection should have a floating input that rejects ground loops, especially a subwoofer which the end user might want some distance from the source componet so someone has likely screwed the pooch here seeing as how so many reports of this are about.

I keep seeing these hum threads but I have never had one of these plate amps in my own hands so I can check it out and say definitively what's what.

I prefer a regular amp myself.

[rickyvance]

I have that amp and I can't MAKE it hum. I would make sure that you are plugging all your mains(for the receiver, amp, and all related components) together in a power strip and you shouldn't have a problem.

RDV

[philiparcario]

Well I remember buying this amp almost 3 years ago and it had a bad hum when plugged into the preout on the amp, so I switched outlets in my apartment and it worked just fine (for the last 3 years). Now I moved to a new a apartment and the hum is back. I'm assuming it's a ground loop problem, I just am not sure how to get rid of it.

I read the reviews on the amp and many other people mentioned the same hum. One guy mentioned "adapter from Walmart and removed the ground lug on that and plugged the amp into it, and the noise vanished." Except I'm not exactly sure what adapter he is talking about. I tried like a ~$50 power strip that said it removed ground loops to no avail. And I'm assuming that 3 years ago I switched the subwoofer to an outlet with no ground (very old house).

Any ideas on what adapter I should buy for the outlet, and how to remove the ground "lug" to get an ungrounded source for the subwoofer?

I tried hooking the woofer up through the cables for the L/R mains and it worked fine with no hum, but I'd really prefer the preout so I can move it to another spot in the room without cables from the mains running over to it.

Thanks for all the help!

how long is your rca sub cable. if it is over 10 feet. get a piece of speaker wire and this volume control
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=300-556

attach one wire in and one wire out then attach those two wire 1 to the sub amp then 1 to the preamp. then turn the volume control you should kill the hum. this is a 25 dollar knock off of a 600 dollar hum buster device. I am giving you a way to come close to this device for 25 dollars. it has less hookups but works on the same idea.

http://www.musicdirect.com/product/73579

[philiparcario]

this is the link that tells you what the and how the 600 dollar device works.

http://www.graniteaudio.com/zero/index.html

if you hook 1 wire to you subplate and that wire to the dayton volume control and take the output wire from the datyon volume control and attach them to you preout component. they are tied together and the resistance can be altered to match.

[johnastockman]

Well I remember buying this amp almost 3 years ago and it had a bad hum when plugged into the preout on the amp, so I switched outlets in my apartment and it worked just fine (for the last 3 years). Now I moved to a new a apartment and the hum is back. I'm assuming it's a ground loop problem, I just am not sure how to get rid of it.

I read the reviews on the amp and many other people mentioned the same hum. One guy mentioned "adapter from Walmart and removed the ground lug on that and plugged the amp into it, and the noise vanished." Except I'm not exactly sure what adapter he is talking about. I tried like a ~$50 power strip that said it removed ground loops to no avail. And I'm assuming that 3 years ago I switched the subwoofer to an outlet with no ground (very old house).

Any ideas on what adapter I should buy for the outlet, and how to remove the ground "lug" to get an ungrounded source for the subwoofer?

I tried hooking the woofer up through the cables for the L/R mains and it worked fine with no hum, but I'd really prefer the preout so I can move it to another spot in the room without cables from the mains running over to it.

Thanks for all the help!

What that guy was referring to is one of those 3-prong to 2-prong adaptors you can get for 99 cents. If you use one, you don't have to remove or cut off the ground lug on the amp's plug. Many will say from a safety standpoint, find the cause of the hum first before you go the "adaptor" route. A few of the subs I've made using that amp had a hum when plugged in at the persons house. All but one was from the incoming cable TV line into the cable box. They had the audio out on the cable box hooked to the AV receiver...when the cable was disconnected from the box, the hum disappeared. A ground-loop isolater for the cable coax solved the hum. The other guy didn't have cable TV, but used one of those adaptors on the amp's power plug and the hum was completely gone.


John A.

[aztd]

Thank you I also did a google and this has alot of information

http://www.epanorama.net/documents/groundloop/

[greysplash]

I had the same issue with the same amp. Its probably a ground loop issue where the amp and receiver are essentially fighting for the same ground which causes them to essentially put a very very small amount of voltage thru the ground which in turn causes the woofer to "hum".
The simplest solution is to not use the ground on the sub amp. You can buy a 3-prong to 2-prong converter for under a buck almost anywhere (CVS, Walgreens, Valu, etc.) This isn't the best solution, but it works and is simple.

Another possible reason could be bad cables, but its most likely the ground.

[biff]

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=180-075