Those of us who have actually done the experiment, switching from either a computer or low quality streamer to a high quality streamer, have heard an unmistakable improvement in sound quality. Even if we don't have the technical know-how to explain it. However, other, smarter people have said it boils down to jitter. Even the best DACs don't eliminate 100% of jitter. Feeding them a signal with less jitter helps DACs reduce jitter more than they could on their own. The very reputable hi-fi company Antipodes used to have a lengthy, very clearly written primer on the subject posted on their site. A cursory check indicates it's no longer there. But they do have a discussion forum that might cover the topic.
Help settle a streaming argument!
This is a SQ argument and is as follows- I argue if you connect your streamer to an outboard DAC the streamer does not matter it’s just serving the music to the outboard DAC to do the work. Therefore, buy a basic streamer. The other is that you need to buy a top quality streamer and DAC to get great SQ.
I liken it to cd players or the more pretentious cd transport argument- if the intent is to connect to outboard DAC the cd player doesn’t matter the outboard DAC DOES!
features and functionality aside! Thoughts…..