Filter tweak for digital backwash?


As my system improves, it’s easier to hear anomalies. The search is now on for a tweak to filter only digital backwash in my AC. The culprit is the regulated transformer power supply (120vac/19vdc converter) to the dedicated laptop for streaming.

The balanced power conditioner has separate outlets for analog and digital. The digital outlets already have built-in filtration for backwash. They work well. But, I need even more. When the laptop is running on its internal battery, the music is very smooth. Unfortunately, the battery life is short. When the laptop is running on the power supply, there’s a slight stridency. When the power supply is plugged in anywhere else, there is huge stridency. So, I’m looking for some gizmo to clean up the digital backwash in-between the conditioner digital outlet and the power cord to the regulated power supply.

I’m not looking for an overall line purifier. The balanced power conditioner does a pretty good job already. Any suggestions?


steakster
randy-11
Why aren't the engineers designing expensive audio gear dealing with these problems?

I thought it was pretty easy to deal with noise ...
I think working to reduce noise is a very tricky business, and I agree with georgelofi that there are more sources of complex noise than ever before. The problem is also compounded by the endless combinations of equipment that can be used with any given component.
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When I see engineers post on various forums, they usually say it is trivial to design noise rejection into a circuit...

Dunno myself.

I'm sure there are more sources of complex noise than ever before but they are usually RF and often in the GHz range so should be even easier to filter out than other "historical" noise.

OTOH, I did see a recent white paper from Intel on USB-C showing significant noise down to DC.


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@steakster 

Noise is a very interesting phenomenon. You can think of it like the canvas of a painting. Just like a different canvas texture or tint could change the visual perception of a painting so too can noise with music or sound. 

Vinyl may be attractive because of the inherent high noise floor and listeners are able to use that background noise to advantage!

We can hear at least 15db below a noise floor!

Sometimes noise will help make some aspects of music more audible.