Have you tried HQPlayer?Good question. I have used HQplayer for a brief trial period. The UI is a bit primitive, but it provides a great learning opportunity to study the effects of filter design on sq. Essentially, one is able to simulate internal DAC operations. But you have to learn the theory first before making good selections for the various filters. A great resource and highly recommended for anyone interested in the topic. I see a lot of people struggle with it.
In my case, I only applied my limited playtime with HQPlayer to a high-quality ESS9018 based DAC and found very few (subjective) differences between the various options. Not enough for me to put up with the poor UI and make it the primary player for everyday use. As an end-point to Roon perhaps it is better suited.
I also think that if one has a high-quality d/s based DAC of recent design, the benefits of using HQPlayer is greatly diminished.
Luisma31, thank you for your comments.