VOX AC4TV Metal Rings

[Johnny_March]

Hello. I was changing the speaker in my VOX AC4TV a few months ago. When I took the chassis out of the cabinet, I notice that the speaker wires and the transformer wires have some strange metal rings slipped over them. Does anyone know what function they serve, if any? I've never seen these rings in another amp before. I'll post a photo of the rings below

img_2507.jpg

[TUBEDUDE]

That's a ferrite ring. Used to filter out R.F. frequencies.

[Johnny_March]

cool. Thanks for that info. How important do you think those ferrite rings are to the performance and design of the amp? I haven't really seen these before and I just wonder why other amps wouldn't use them if they're another added measure of removing unwanted frequencies.

[TUBEDUDE]

If you build to a higher standard filtering input power is common. Usually in a filter module or built into the IEC socket. I've used stacks of the smaller rings on the signal input wire. Amps built to a price point may not use any filtering. I think it's worth reducing R.F. in the chassis.

[Stevem]

Ah, once again the repercussions of building a amp with circuit board type construction and no shielded wiring!

[Kagliostro]

if they hadn't had any problems they would have saved the cost of the wounded ones, since they had put them on, they would have had some reason, don't you think ?

Franco

[imjonwain]

Depends how much testing they can do in house. EMC rules vary so much around the world sometimes you do everything out of the box for any potential issue that might come up before evening going to testing. It's cheaper to just add the parts initially than to deal with possible costs and time loss from failing & repeating EMC testing or "remotely possible" risks that could cause issues in some markets down the line. Engineers don't get anywhere near the final say on that stuff.