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Discussion Starter #1
looking for a little help/advise on a pair of mythos sts towers i recently purchased used, i tried to research the topic but couldnt get any "definitive" (get it, definitive?) answers:

-after setup i was getting humming noise from one of the subs, i unplugged the speaker from the wall and the hum went away but the sub obviously stopped working but the speakers in that tower work just fine.

-i disconnected the speaker from the tower and plugged it back into another outlet on another circuit and when it was plugged in the sub still hummed (there was no connection to the receiver, just plugged the speaker in)

-i tried a different power cord and still got the humming sound so i think i've ruled out any issues w/ my receiver, household power/circuits and the power cord so there must be an issue internally w/in the tower.

can anyone offer any repair advise or thoughts? i'm also located in Chicago FYI if anyone knows a good/honest tech in the area.

thanks for the help!
 

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looking for a little help/advise on a pair of mythos sts towers i recently purchased used, i tried to research the topic but couldnt get any "definitive" (get it, definitive?) answers:

-after setup i was getting humming noise from one of the subs, i unplugged the speaker from the wall and the hum went away but the sub obviously stopped working but the speakers in that tower work just fine.

-i disconnected the speaker from the tower and plugged it back into another outlet on another circuit and when it was plugged in the sub still hummed (there was no connection to the receiver, just plugged the speaker in)

-i tried a different power cord and still got the humming sound so i think i've ruled out any issues w/ my receiver, household power/circuits and the power cord so there must be an issue internally w/in the tower.

can anyone offer any repair advise or thoughts? i'm also located in Chicago FYI if anyone knows a good/honest tech in the area.

thanks for the help!
I'm a little confused in "disconnected the speaker from the tower"

But regardless, you seem to be only getting the hum through the sub portion of the tower, so it's either the amp in the speaker or your connection to the receiver.
How do you have them wired, speaker wire only or with speaker wire and coax?
The subs will still work with speaker wire only, so if you connect that way and you still get the hum, the problem is in the amp in the speaker. If it goes away them the problem is either in the cable your using to connect the Low Level to your receiver -or- the output from your receiver itself, or the input on the speaker.

If it ends up that the problem is in the internal amp, e-mail DefTech, they'll most likely just send you an amp (doesn't matter how old they are or if you're the original owner, their customer service and warranty is that good) then you'll either just have to swap it out, our find someone to do it for you, but they are just plug-n-play, pretty simple to do.
 

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Oh, let me add to this a little bit.
If you get no hum with speaker wire only, then you of course will try swapping the cables and the position of the connection to your receiver. If you swap everything around in all the combinations you can think of and it still appears to be "that speaker" only, also let DefTech know this, because it could be a bad low level connection in the speaker and not ness. the amp I'm the speaker, I'm not sure about those, but in most of the older models with built in amps, the amps are not directly connected to the board with the connection and crossovers, they are two separate pieces, this will help them to know what to send you.
 

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looking for a little help/advise on a pair of mythos sts towers i recently purchased used, i tried to research the topic but couldnt get any "definitive" (get it, definitive?) answers:

-after setup i was getting humming noise from one of the subs, i unplugged the speaker from the wall and the hum went away but the sub obviously stopped working but the speakers in that tower work just fine.

-i disconnected the speaker from the tower and plugged it back into another outlet on another circuit and when it was plugged in the sub still hummed (there was no connection to the receiver, just plugged the speaker in)

-i tried a different power cord and still got the humming sound so i think i've ruled out any issues w/ my receiver, household power/circuits and the power cord so there must be an issue internally w/in the tower.

can anyone offer any repair advise or thoughts? i'm also located in Chicago FYI if anyone knows a good/honest tech in the area.

thanks for the help!
Make sure everything is plugged into the same wall circuit. If you have to use an extension cord to accomplish this, then do so. Sounds like a 60Hz hum from bad grounding ... i.e. a ground loop.
 

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Sounds like it could be a ground loop problem, which, if it is, is not because of the speaker being broken in any way. One way to quickly discover if it is something with the electrical in the home is to get whats often called a cheater plug from a hardware store, to test that theory out. You plug the cheater plug into the wall, then the speaker into that. If the hum goes away, it is a grounding issue. Others will chime in on the fact that just using the cheater plug and leaving it is not the answer as the speaker will no longer be grounded and can be dangerous. it is just as a test.
 

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Discussion Starter #7
I have the identical problem. Have you found a solution?

after trying every possible connection that would rule out bad cables or an issue w/ my receiver i called def tech and they sent me a new amp. it cost around $100 shipped and it did come w/ installation instructions. i'm handy but i've never opened up a speaker/sub before and this was an easy job for me. took about an hour total and i took my time with the process.

prior to calling def tech i did take the speaker to a repair shop in Chicago so i could rule out any loose internal wiring or a bad ground...upon inspection i was told that the internal amp for the sub was the issue.

works/sounds perfect now!
 
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