It sounds to me, like you are not looking for a dedicated streamer or network player, but just want high quality output, while streaming online content from your desktop PC.
Not certain if the question is related to grabbing signal from audio-out cable from soundcard vs pulling audio from USB.
I also frequently stream audio while working on my desktop. I have tried a few different arrangements. I Have used powered stereo speakers first with integrated and then with aftermarket sound card. Then I switched from powered speakers to passive speakers and used several different desktop mini amplifier setups, with increasingly upgraded passive speakers. I tried the passive speakers with desktop amplifier, after going first through a DAC. I dont think the DAC gave much if anything over the aftermarket soundcard.
I think of all the above steps, what improved my enjoyment most was the switch from powered to passive speakers, followed secondly by the addition of an aftermarket dedicated soundcard.
The benefits of powered speakers are simplicity and less clutter. Power cord to wall, audio cable to desktop, done, but I think the performance per dollar ratio is much higher with passive speakers.
I can't say the sound quality difference from integrated audio to aftermarket upgrade card was huge, but the features and adjustment of the associated software were beneficial and added some enjoyment, and some sound improvement, possibly even justas result of having dedicated filtering in place and removing some electronic noise.
On that note, there are many people that are firm believers that a power filter between wall and computer can make an audible difference. My computer is connected to a power conditioner but I haven't tested that for any audible changes.
The switch from powered speakers to passive was the largest improvement in sound quality and made repurposing and replacing speakers much easier.
I can't get in to what type of amp or amp/dac combo because that would derail the whole discussion, but I would say skip anything under about $80, and as you get close to the $150 to $220 range there are lots of great options. Don't even bother to ask which, just find something in that price bracket with strong comparative reviews and you will be happy.
Someone will yell at me for saying this but I have had great results with aftermarket sound card straight to power amplifier, and even using a reasonable quality DAC such as the topping D50s most recently, I can't say that the DAC was as significant of a factor if at all, compared to speaker selection. Also, raising your speakers even 4 inches off of desktop, even with makeshift stands will increase your Soundstage and they will sound better.
I dont know if any of that helps but those have been my experiences. Add a sound card, add a desktop amp, get better speakers.
Elon
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