hissing sound coming from behind woofer on one side AR11

Sorry if you have been labeled a troll. You seem to have enough sense to effect a repair so please do.

I wouldn't bet on it and I'm not going back through the thread because I don't thread or keep or watch articles but, I thought Amanda said the speaker hissed on its own without an amp powered up.

If you do effect a repair, please let us know what the problem was. I would be delighted to learn that I was wrong.

My memory is that she said it didn't -- the amp had to be on. But there seemed to be no correlation between the program's content or volume.

Put a 'scope on the amp's output, if you can.

1: Google doesn't allow any attachments.

2: This is not a binaries newsgroup so any message with an attachment won't propagate to most news servers.

You think she has a MRI machine in her wall? The voice coil isn't going to be affected by nearby magnetic fields, due to the narrow gap and shielding.

I thought it was from BEHIND the speaker.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I once lived in an old mansion that had been converted into an apartment building where one of my KLH 32 speakers was mounted by the main electrical entrance for the building. There sometimes was a soft noise from the tweeter without the amplifier being on. Later on we discovered that the owner of the building had replaced one of the cartridge fuses in series with the hot 120 AC in with a piece of copper pipe that was arcing at the fuse clips. I know this sounds apocryphal but I spent 32 years in the consumer audio field as a technician, and service and store manager so you can be reasonably sure, in this case, that I'm not a troll . Chuck

What do you think formed the "return path" that allowed current to flow through the speaker?

For example... In the simplest possible 2-way system, with only a capacitor in series with the tweeter, * there would be no complete circuit for the current to flow through the tweeter, unless the unpowered amplifier had a sufficiently low output impedance.

• The woofer can be designed to mechanically roll off at the crossover frequency, so no inductor is needed.

or

The tweeter, capacitor and woofer are all effectively in series as a loop in the speaker box, and that loop is large enough to pick up the high M field spectrum of the arcing 60Hz so close by. Some of that generated arc noise will fall in the band that the tweeter will reproduce efficiently.

Neil S.

An old friend used to live within a hundred feet of a radio station. He swears that on one occasion he could hear programming coming from a filling in one of his molars.

Duh. I should surrender my BSEE.

This is quite common. The BBC used to operated a long wave transmitter in the county where I live. It was 200kW during the daylight hours, and 470kW at night. There were always reports in the local newspaper of people experiencing oddball reception events, and picking up radio 'in your head' was a regular one. Apparently, it happens more when fillings are new, and the oxide layers or what have you, are still building. Supposedly, the filling acts as a simple diode detector, and if the field strength is high enough, actually 'rattles' mechanically. The vibration from this passes out of the tooth and up the jawbone into the skull, where it is picked up directly by the ears. I have also seen the phenomenon explained as the detected audio voltage passing out of the tooth, and directly stimulating nerves that are part of the hearing centre. I suppose that's possible, but it sounds less likely to me, than the first explanation.

Another few favourites for 'ghost' reception near this transmitter, were electric cookers, stereo systems that were turned off, and mattress springs !!

Arfa

So Amanda may live near a 500kw transmitter that plays wildlife sounds. That would explain the snake hissing behind her speaker.

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WLW in Cincinnati, Ohio used to run 500 KW on 700 KHz under an experimental license. Local farmers reported talking and singing fence wire or a few miles from their tower.

has some photos and a description, along with a simplified schematic of the beast. It also has one of the few remaining Blaw-Knox diamond towers.

WSM in Nashville has another Blaw-Knox tower.

In the house where we lived some years ago, we used to get 'fax machine' noises from the bedside lamp during the night. Happily it only happened when it was switched on.

Ron(UK)

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Did they hear it when they weren't relieving themselves?

"Mythbusters" did a segment on this, referencing a claim by Lucille Ball of having heard radio signals in her head during the '40s. Adam and Jamie did an uncharacteristically shallow investigation, and were unable to confirm the effect.

Whilst it's undoubtedly an entertaining show to watch, I do sometimes find the science to be a little 'questionable', probably because of a need to ensure entertainment value for the network. At the end of the day, almost anything will work as a simple diode detector, and I see no reason why that shouldn't be true of an amalgam tooth filling, which is a fairly complex layered structure, sitting in a conductive liquid. To be fair, I'm pretty sure that when I first looked into this effect many years ago, whatever I was reading suggested that it was particularly related to 'new' fillings. This may well be the case, as new fillings have that very metallic taste that is actually, I understand, them acting as a tiny battery, and giving the tongue a mild electric shock, which the brain translates as a 'taste' as the nerves are being stimulated directly. 470kW of AM must result in a mother of a high field strength in the locality.

Arfa