I dug out my box of random inductors and tried to quieten one of the LED dimmers today. Contrary to what I thought in my previous post, the coils actually worked best when installed in series between the dimmer and the LED load. Almost all the inductors I tried helped quieten the chopping noise heard on my headphone amp. One interestingly completely stopped the noise when dimmed at 0%/50%/100%, but was still slightly audible at the in-between settings:
Two of the inductors were able to completely remove the noise. This one, and a very similar looking one:
Yay, I can listen to my headphones and dim my lights at the same time now! I love simple solutions :)
The other inductor that removed all the noise looks very similar but it’s slightly smaller. I might actually be able to fit it into the other dimmer module, to solve the noise on my speaker amp.