Branstylad(Mostly Harmless) posted this on Friday, 21st November 2003, 19:55
I bought a Sony HTDDW750 home theatre package last week to upgrade my current system and I`m very impressed. However when I turn on the Sub-woofer there is an immeadiate humming sound that comes from the sub-woofer. Once the receiver or DVD are up and running you can`t hear the humming sound. Can anyone tell me whether the sub-woofer should be totally silent when switched on or is a slight hum acceptable? I bought the system from Digital Point and on contacting them was told there wasn`t a problem. On visiting a Sony Centre today they told me there should be no noise on switch on? Any help much appreciated. Cheers, Colin.
RE: Any Sub-Woofer Guru`s Out There?
Superted(Elite) posted this on Saturday, 22nd November 2003, 14:35
No there shouldn`t be any noise.
It sounds as though you are suffering from mains hum, it is caused when your sub, amp, devices or leads are close to a mains cable and are picking up the sine wave signal generated by the mains.
It is easy to fix, try moving the audio cables about, as far away from mains leads and your tv as possible, one trick is, as it is impossible to get them completely away from a mains lead, run them underneath it as for some reason they are less likely to pick it up.
If that doesn`t fix it, try disconnecting and re-connecting one cable at a time to see if it goes, it is probably only being picked up by one lead, just you only notice it on the sub. Once you find the right one, try moving it, if that doesn`t help, replace it with a sheilded lead which will help block the signal.
It`s more than likely due to the crap leads supplied with the system (Sony`s cables are notoriously low-end) - invest in a good quality fully shielded cable as mentioned above and Robert`s your Mother`s brother. See my link below, I had the same problem.
Branstylad(Mostly Harmless) posted this on Monday, 24th November 2003, 00:40
Thanks for the feedback guys ( no pun intended ). Since my posting I have taken the sub woofer into another room and plugged it into another wall socket away from any other electrical equipment . Guess what? The hum is still there. Also if you turn the volume up and tap on the input you can get a very good morse code effect? Does this point to the problem being the sub woofer rather than cables / routing? Colin.
I still recommend you invest in a decent shielded cable - the standard cables supplied with a lot of hi-fi equipment are usually crap. There`s no point investing in a quality sound system and then use poor quality cables with them. I usually set aside between 10 - 15% of my budget for cables. One of these should sort you out:
