Logitech Z560 amp hums?

[kinney]

Just like the title, my z560 amp hums sometimes even when turned off. Sound quality has been unaffected and it only does it once in a great while.
Its a quiet hum but gets louder then softer again. Is this a sign of a failing amp?

I've never used them at any volume level since I've bought them, maybe once or twice but I dont give them any workout.

If they quit I guess this is what I get for not going klipsch eh?

Athlon 1700+, Epox 8RDA (NForce2), Maxtor Diamondmax Plus 9 80GB 8MB cache, 2x256mb Crucial PC2100 in Dual DDR, Geforce 3, Audigy, Z560s, MX500

 

[david__t]

I get the same hum from my Altec Lansing 2100s all the time and it is so annoying that I have to switch them off at the wall when not using them. I first thought that it was due to poor signal quality or interferance but I now think that it is just a case of poor shielding in the subwoofer - I think that the tranformer causes the hum in the speakers or maybe the transformer itself is the problem.

I have some Altec 621s as well and they are fine but lots of speakers do this in my experience. In some cases I can put it down to signal quality (which makes my expensive Yamaha sub have a very quiet hum when on but not in use) but others I think are caused by poor shielding or poor transformers.

I too would be interested to hear what other people think about humming and why they think it happens in their cases.

4.77MHz to 4.0GHz in 10 years. Imagine the space year 2020

 

[Syndil]

I have a set of Altec Lansing 641's. When I first bought them, the amp would hum slightly even when they were powered off. It was a very quiet hum, probaby quieter than most people would care about or even notice, but I have very sensitive hearing and it bothered me when I was trying to sleep. The only way to silence the hum was by flipping the switch on the rear of the sub to completely cut power to the amp. However after several months of use, the amp did finally die leaving me with no bass. The speakers were still under warranty so I returned them to Altec, and they sent me a new set of 641's. They do not hum at all, and have already far outlasted the first set. So in my case, I think I just got a bad amp the first time around, explaining the hum. But there are indeed many things that can cause an amp to hum, so in your case it could just be poor shielding, cheap components, etc. I think I read elsewhere in this forum that the wires in the Z560 are ony 18 guage (can't find the thread, any help here?), which would make them very susceptible to interference.

<font color=white><b>_________________________________________________</font color=white></b>
Armadillo<font color=orange>[</font color=orange><font color=green>TcC</font color=green><font color=orange>]</font color=orange> at Lanwar and MML