Manufacturers maybe, but I certainly had a debate with an otherwise well informed expert who really didn't understand the problem, and therefore assumed it must just be Internet misinformation.
I couldn't convince him that it was real, he just criticised my belief in audio "myths"!
Unfortunately we permanently have to be aware that it isn't that easy nowadays to tell facts from fiction, see The Club of Rome, Earth for All, Sept. 2022.
Best regards!
Best regards!
The picture you linked is from the Wikipedia article that I already linked to...before you even posted!
So you don't need to tell me to read the article, I was the one who referenced it.
I already said that I put a turn inside a coil, as in the picture.
But you miss the point, it's not a feasible approach for a transformer, and that's what the OP asked about.
It's totally impractical to unwind a transformer, dismantle the laminated core to put a return wire inside.
I did it on an air cored inductor, only to attempt to convince a know-all that the theory was correct, as I mentioned in the previous post.
Best wishes
David
Add 220uF of bipolar capacitor into either of the probe leads in that first diagram: and all concerns for preserving the headphones go-away.
That could be as simple as two 470uF parts out of the scrap bin, back-to-back, for all this circuit needs to do.
(and I agree: something like that crude setup can be sometimes prove useful to have to hand, on the bench. I save v cheap old wired earbuds for this kind of thing.)