I bought a cheap EL wire from Amazon. A lot or reviews mark EL wire down because of the high pitched whine the battery unit emits when the EL wire is lit up. I thought perhaps I could do something about that. I needed one for a small project which has required taking the battery unit apart. I've got the small PCB out and removed the LED. The little yellow transformer does indeed make a very high pitched whine - very noticeable, which would drive anyone hearing it utterly insane like some kind of high-tech torture device.

So what are my options? Encase the transformer in hot glue and hope it drowns out the noise? Or can I replace it with something better than doesn't make such a godawful racket? What sort of transformer do I need?

 

There's no simple electronic cure. The transformer is a major part of an oscillator circuit which steps up the battery voltage. It would require a transformer re-design to raise the oscillator frequency into the inaudible ultrasonic range.
You could try enclosing the whole unit in sound-absorbing wadding, but would need to monitor it to ensure it doesn't overheat.

 

I see. I wasn't sure if it were possible to replace the transformer for a better one, one that isn't obviously cheap. Would covering the entire circuit and transformer with hot glue drown out the noise?

 

I don't think it would reduce the noise much, unless applied extremely thickly. There are sure to be better sound-absorbing materials (check with Google).

 

In the past, I had access to a variety of EL wire drivers. Some of them were really noisy but others not much. (I had to ask because one of my ears perceive just noise but confusedly while the other is impaired as well).

More than 10 years I do nothing with them but I recall being different designs supposed to corresponds to the specific wire color, thus the different frequencies.

All of them seemed rather cheap. Tried to encase the culprit in different "boxes" made of styrofoam, telgopor and similar materials. Noise was still there.

 

El wire operates best at 1to 2 KHz. Lower reduces light output, higher results in heating.

I would try spray on foam insulation to absorb the sound. I recently bought a unit off Amazon as well and I cannot hear it at all, but then my hearing is pretty bad these days.

Bob

 

It would require a transformer re-design to raise the oscillator frequency into the inaudible ultrasonic range.

Not for EL. The brightness is a function of frequency and they typically can’t take more than 3KHz or so. They operate smack dab in the audible range, 200-2000Hz.

 

In an other forum i read, it's the coils of the transformer, and you can't better wind it, there will always be tiny gaps enabling vibration.
If that is true, you could plunge it into resin, and put the bath under vacuum. Then all the gaps should be filled with this resin, and as it hardens, the sound should be gone.

 

If there is any detectable vibration, as in touching the transformer outer casing, a possible improvement would be to use an adhesive to fasten a metallic mass of some type to the casing surface. The frequency of the noise associated with the vibration should be lowered, resulting in a noise that is not quite as irritating. The effect of the added mass depends on the extent that the transformer case is involved in the actual vibration.

 

Has anyone ever tried RTV rubber? As it is flexible, but not acidic like silicone, it may better absorb the hf sound. RTV (Room Temperature Vulcanizing Rubber) is used in crafts to make detailed molds.

 

This is an old thread revived by a first-time poster. I wouldn't waste time on it.
My EL transformer, an old wall wart run in reverse, makes noise. Putting rubbery foam between it and the enclosure knocked the sound down so much that it's no longer an issue.

 

I bought a cheap EL wire from Amazon. A lot or reviews mark EL wire down because of the high pitched whine the battery unit emits when the EL wire is lit up. I thought perhaps I could do something about that. I needed one for a small project which has required taking the battery unit apart. I've got the small PCB out and removed the LED. The little yellow transformer does indeed make a very high pitched whine - very noticeable, which would drive anyone hearing it utterly insane like some kind of high-tech torture device.

So what are my options? Encase the transformer in hot glue and hope it drowns out the noise? Or can I replace it with something better than doesn't make such a godawful racket? What sort of transformer do I need?

The really simple way to quiet the transformer is to encase it in a glob of RTV silicone material. That material, when properly applied, will dampen the vibrations quite well. You will need a case to hold a shape while the material is curing, which will take a few hours. You will also need to bypass that switch and add external leads for the power because once the thing is encased it will not be acessable. And be sure to use the electrical grade of silicone RTV material.