PO89ZB , an inline DC filter for SMPS wall warts . Preamps, HPA, Korg NuTube, etc

Just have a look at your power brick from the Laptop, I am pretty sure you are exceeding 3A....

That said why would the laptop be in charge when using it to play music ? If I was doing what you are doing I would listen with the charger disconnected ?

Or do you use the laptop brick to power another device like Preamp ?

Sorry for the confusion...
 
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If you are a self-sufficient, brave, confident, and experienced DIY builder, you could use the SMPS filter design which Nelson Pass created for his DIY VFET project. That project draws a total of about 4 amps from the SMPS, and his filter circuit design specifies a Bourns inductor which is rated for 5 amps.

You'd either lay out your own PCB for it, or else build the circuit on vectorboard with beefy point to point wiring.


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I am going out on a limb here but the filter has no inherent sound quality. I am using five currently and all they do is allow less noise to reach the audio device via the DC power connection. Any change in perceived sound quality for a connected device is only due to a lower noise floor on the power supply. It is curious that the filter has created negative changes to the sound quality of the audio output of your laptop.
 
Merlin,

Mark kindly hinted you towards a possible and simple solution. It is obviously inspirational and you really need to know what you are doing before getting started. I guess under load you mean output of the filter, and if so it isn't the LED, but is rather around C1 (so +V output is not quite where you believe.)

LED, R1 and thermistor are obviously not required if just "thinking simple filter" block.

I hope this helps

Claude