SBLs buzz when not plugged in

Posted by: connon price on 28 September 2003

Has anyone seen this? I had my SBLs unplugged and happened to put my ear by the tweeter and heard a sixty hz buzz. I have a lamp plugged into a dimmer that is plugged into the wall against which the SBLs sit. I know that dimmers can cause noise in the mains, but this was rediculous. The SBLs are on chips so I slid it away from the wall and it stopped buzzing at about 18 inches. The old nob and tube (1941 construction) wiring is on that particular circuit that passes behind the speaker in the wall. Is that a big electro magnetic field that is swamping the cross over on the back of the SBLs and creating a current in the speakers? Weird.

Anyone explain that for me?

Connon

Posted on: 29 September 2003 by Noel

Connon,
when you say unplugged, where abouts have you taken the leads out? have you taken the leads out from the back of the speakers and/or from the x-over to the drive units? Yes, you can get EMF pollution from cables inthe wall, but also by being close to junction boxes and meter units.
Noel.

Posted on: 29 September 2003 by greeny

Clearly you have a bee stuck inside. I hear Old SBL boxes are often used as Hives and this poor fellow obviously got somewhat confused!!

Posted on: 29 September 2003 by Rasher

Twilight Zone. It's aliens.
Tom, was the police radio broadcast from another time?
Connon - Try Ghostbusters

Posted on: 29 September 2003 by domfjbrown

My (crappy) centre speaker does this if on top of a Sony TV (but not my housemate's Misubishi - oddly enough).

My Mordaunt-Short MS25is used to make good aerials for taxis and mobile phones (you could hear the GSM burst pulses clear as day through them).

It's something to do with the way the crossovers/internal wiring is arranged - I'm sure of it - as you only need a tiny signal (RFI or other) to excite a tweeter's voicecoil.

Make your choice, adventurous Stranger;
Strike the bell and bide the danger
Or wonder, till it drives you mad,
What would have followed if you had.

Posted on: 29 September 2003 by prowla

You've heard of SETI, right?
Well it so happens that the aliens have decided to use your speakers as the means to communicate with the earthlings!

Paul Rowlands

Posted on: 29 September 2003 by connon price

Thanks all, I did have a wasps nest in the tree on the other side of the wall this summer...

Noel, the speaker wire was detatched at the cross over but the cross over was still plugged into the drive units.