How to silence an EL Wire AC Inverter?

[John_NY]

I'll have to wait a bit before I post any pictures -- my EL Inverter from Adafruit is in transit, as is the 9V slide-switch inverter. I'll try to remember to update the thread when they arrive (probably < 5 days). It might be OBE, now that I see westfw's schematic.

-John

[stinkbutt]

There are a slew of boost controller IC's that can handle this as well. As for the inverter bit, well, once you've dispensed with the microcontroller in favor of a boost IC, you might as well go old school and just use a 555.

[paulharmo]

Sorry to revive this thread, but does anyone have any more insight on this project? Are there purchasable inverters that don't squeal like a stuck pig, or is this purely a homebrew project? I'd like to try to silence one of the "adafruit" style inverters, but I'm worried that that may not do the trick. I'm going to have to either have the inverter running basically next to my ear, or *possibly* massively extend the cable to fit in a backpack or something of that sort. If I went that far, though, I'd be making a custom enclosure/battery setup for the lot. I'd prefer to use 12v in that case.

-Paul

[adafruit]

Sorry to revive this thread, but does anyone have any more insight on this project? Are there purchasable inverters that don't squeal like a stuck pig, or is this purely a homebrew project? I'd like to try to silence one of the "adafruit" style inverters, but I'm worried that that may not do the trick. I'm going to have to either have the inverter running basically next to my ear, or *possibly* massively extend the cable to fit in a backpack or something of that sort. If I went that far, though, I'd be making a custom enclosure/battery setup for the lot. I'd prefer to use 12v in that case.
-Paul

hi paul,

we believe these are the best high-quality inverters that are available - we sampled all the ones that were out there and chose the ones we did after careful testing.

you're welcome to purchase one and return it within 14 days if this is a concern.

cheers,
adafruit

[paulharmo]

Thanks for the quick reply!

My friend has 3 inverters of the exact same design you guys sell, and I agree, they are of high quality. However I'm looking for an inverter that will run on a 12v system. Is there a simple modification that can be done to the PCB to make it run on 12v?

-P

[adafruit]

Is there a simple modification that can be done to the PCB to make it run on 12v?

no, but we will have a 12v inverter in the store either this week or early next week

cheers,
adafruit

[GranitePenguin]

I finally got around to soldering my EL wire starter kit (yes, it's a pre-already-connected kit). I love the look of it, but wasn't quite prepared for the whining sound. In the description of the kit, it's mentioned that foam tape is included (which it is) to place inside to dampen the noise.

Where, exactly, are you expected to insert the foam tape? Inside the battery case(which doesn't make a lot of sense) or inside the components area (since that is where the noise comes from)?

If you put it inside the electronics compartment, there isn't a lot of room. Plus, is it safe to cram foam into the compartment (any heat issues)?

Thanks.

[adafruit_support_bill]

These don't run very hot so there is no real heat issue. The compressed foam will help damp the vibration from the components.

[GranitePenguin]

Thanks.

I crammed the foam into every spare space I could find, and it doesn't seem to be helping much at all.

On the plus side, it dissipates with distance pretty quickly.

Is the whine just something that you basically have to live with when dealing with EL ?

[adafruit]

yes

[rwinscot]

With the space available in that pocket inverter... you may have to "deal with the squeal." Do you think you could make a little more space for say... a sound cancellation circuit?

The whine is, for the most part, consistent which means that the same sound - broadcast out of phase from within the enclosure should make for a significant reduction of whine for your passers-by.

Rick Winscot

[adafruit]

rwinscot, sound cancellation doesn't really work that way. the best solution is to pad the circuit - every EL inverter we have ever seen makes a noise

[W9TIM]

I noticed that the IOS flowing wire EL enhanced USB adapter is silent! in contrast to the other inverters. - is it just the low power draw that keeps it quiet or does this product have a secret to keeping it from squealing?