A couple of questions

[speed3]

Finally, after about 5 months of sitting in boxes I was able to hook my home theater up in my new house this past weekend and was pretty excited to fire up a movie. Unfortunately, I have a very audible hum coming from my sub right now. I can hear it from across the room!! The gain is set at 4 of 10 and the hum increases when the gain is turned up and vice versa. The hum also increases when I turn my receiver on. All of my components are connected to the same outlet, I have nothing else plugged into the circuit, and I do not have a cable box, or cable for that matter. Obviously, it seems that I have a ground loop issue. I read the posts in the archives concerning this and the cheapest and easiest thing I have found is to use a cheater plug on the sub. Is this a bad idea. Since the sub does not have auto turn on I must manually switch it each time I use it so I am a little worried about it not being grounded. Is this legitimate?

On another note, my brother-in-law has a "Dolby Digital Ready" receiver with a Sony DVD player with a built in decoder. He has asked for cables for Christmas to hook the decoder up to the receiver. I remember that they used to sell packaged cable systems for this purpose, but now I can't find any. Anyone have any help as to where I can find them?

Thanks in advance for the help.

[jtkinney]

If you are using a low level input to the sub, check to make sure they are plugged in all the way. If they are, try swapping cables. Also, try disconnecting the sub from the receiver and see if the hum is still there and coming in the power line.

[DrWho]

if the cheater plug works then i'd use it. you also might wanna check through your system and isolate what's causing the buzz (if the ground lift doesn't work). so if your sub doesn't hum when everything else is turned off, trace the circuit back and turn stuff on until you find the buzz.

[dougdrake]

Speed - I had the same problem in my system, and it turned out to be my VCR (I don't have cable, either.) I found this by unplugging each source component until the hum stopped. In my case, I solved it by removing the electrical connections from my video sources to my audio system -- they are now connected with fiber optics (even my VCR).

If you are using a 5.1 decoder, you'll basically need 6 cables. I'd suggest looking at the Radio Shack Gold a/v interconnects or component video cables. They are all shielded coax (even the audio connection) and come with the 3 cables (audio left/right and video) bound together. Get two of those and you should be all set.

DD

[T2K]

I had pretty much the same setup you have before changing a couple years ago. At my prior house I had the same problem. I used the cheater plug (and I always unplug my subs when they're not being used), Acoustic Research sub cables( www.accessories4less.com ) and the Mondial Magic Box. Both there and at my present home I had no further problems.

Try the above recommendations and keep asking questions if you don't resolve the problem. Good luck, and its gonna sound good!

Keith

[T2K]

Try the cheater and change the sub cable. Use a short one temporarily if thats all you have on hand for test purposes. Are the DefTechs powered?

I have my SW12II's set at '7', if that helps.

Keith

[speed3]

Thanks everyone. The sub hums even with all of the other components off, etc. I threw in a cheater plug last night and my sub dropped dead silent. I guess the $0.47 investment was worth it!! I have a feeling that the electrical system itself may be to blame. The house was built in the early 30's and I've found countless wiring mistakes in the house from DIY'ers over the years that didn't know what they were doing (or didn't undertand the ramifications of reverse polarity, etc.). Level 7 on your SW12II!?! I bumped it up to 5 last night now that the hum is gone. I've had it up around 7 before, but my wife would strangle me at 7!!

[dougdrake]

speed - just to clarify...if you want to isolate the hum, you'll need to disconnect the source components, not merely have them turned off (if that's what you meant)

DD

[T2K]

That's right speed. My subs are not placed in corners as the only corner I have available I use to occasionally stand in when my wife gets pi$$ed about me buying audio equipment.

The sub placement does not offer the best low end response but does seem to even out the response in room, when used along with the four other 12" built-in subs in my KSP300's.

Klipsch included a cheater plug with the SW series subs (others too I'm sure) and I've always used them with good results. Of course I always unplug my subs when they're not being used because its just easier than repairing them after a surge/lightening strike.

Glad to hear you've solved your problems!

Keith

[speed3]

Yes, I meant that I disconnected all of the components and was still getting the hum. Definitely bad wiring. Sorry for the confusion.

Keith, my sub is also not in the corner but along the front wall. I agree that the response suffers in this configuration. Thankfully, it's a fairly small room so the gain can remain a little lower. I wasn't aware that the SW's came with cheaters since I bought mine as a "demo" from a shop that was going out of business. I was able to pick it up for $450 back in 1995 when most places wanted considerably more for them. It makes me feel a little better knowing that they used to sell them with the plugs, however, I also am fully aware that the sub is not properly grounded.