AmyAlice: DC filter for SMPS, using 2 feedthru capacitors + SMD assembly. max 3A & max 48V

I just measured a few Kemets (ESH477M050AH4AA) vs a Nichicon, it could be my batch:
 

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Forgot to write here 😅 Works as intended, awesome for smps powered devices round the house 🙂 Smaller footprint than original, added led for flair. Will increase footprint size a bit for some components for ease of hand soldering.



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When you place the two inductors next to each other they couple (like a transformer). Even though "K" is low, it still effects the filter function. You can demonstrate this for yourself in LTSpice.

In ham radio land, the inductors of cascaded filters are either compartmentalized, or placed at right angles.
 
You could unsolder one of the inductors, rotate it 180 degrees, and solder it back again. (You've just swapped the "phase dots" of the transformer.) Now any magnetic coupling which might exist, produces the opposite phase electrical behavior. If magnetic coupling exists to a significant degree, you'll see an electrical difference before/after rotating.
 
I have been using the AmyAlice with my ACP+ and ACAMini combine and have been very happy with what it has done. I was using the excellent SMPS DC Filter P089ZB, but when I changed it out for the AmyAlice I noticed, what I would call a drop in the noise floor. The power supply noise that was getting through the P089ZB was possibly masking some of the low level music. The change for me is as if there is a little more dynamics to the music.

You milage may vary, but it is will worth the effort to give the AmyAlice a try.

Mark, Thank you very much for the AmyAlice filer