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

I only had a chance to listen for a couple of minutes. Initial impressions are positive and worth putting it front of the ACA Mini.

I did secure the AmyAlice to the caps. You can see what I did in the picture.

I did use a P089ZB with the amp before, and still think that there was an improvement. That just could be new poppa syndrome, but don’t think so.

IMG_5510.jpeg
 
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... as Forum readers are well aware, there are lots of new electronic components which are offered ONLY in SMD packages. High volume electronics manufacturing is all-SMD in Y2023, therefore component suppliers meet their customers' needs with all-SMD parts. This is particularly true of new components, which, by the very definition of the word "new", do not exist in legacy thru-hole designs. ... A couple of new, SMD-only components are now available, which enable much better performance (i.e. greater noise attenuation) in SMPS DC filters.

This may explain why members prefer AmyAlice
 
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AmyAlice builders and thread readers might also be interested in a new Forum discussion thread which was recently created:


Forum member @schultzsch has laid out a new PCB which includes the AmyAlice DC filter and a capacitance multiplier using bipolar transistors. PCB manufacturing Gerber files are freely downloadable. Take a look if you are interested.
 
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Hey guys
I tried to build a filter using SMD + discrete components. Make the most of the components you already have.
I changed the circuit slightly and added a common-mode rejection inductor in front of it.
I had two switching power supplies in my hands for testing, and they were so noisy that I couldn't use them to measure the THD+N of the amplifier.
It's time to try an external filter. I'll share the final results below in a few days. Hope all the best.:p
 
Progress report and a question or two:

Finished the first of my boards. It was much easier than my earlier experiences with the large pads. I'll clean it up in the morning and grab a picture. The Floor Monster claimed only one resistor.

Fifteen years or so ago, I built a Hagerman Bugle, and he included similar instructions on board/flux cleanup, suggesting submersion in isopropyl alcohol in a shallow dish up to the board top surface for while and scrubbing a couple of times. Is there a time of alcohol exposure issue with any devices, active or passive, cleaning up this way. Alternatively, are there commercial cleaners worth using. I've never had a problem with the submersion over perhaps 15 builds.

I metered the resistors and the smd caps after soldering,and all seems well. I think the diodes are right though the faint symbology is mildy ambiguous. Any useful checks I should make?

Thanks,

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