@richardbrand The source material matters, but if the equipment isn't up to the task of extracting the information from the media, the sound quality isn't going to be as good as it could be with a high quality external (or internal) DAC converting the digital to analog.
I have many SACDs and if I play the SACD in my Oppo player and the sound from the internal DAC in the Oppo is clearly worse than if I play the red book version from the same SACD disc in the CD player in my Rockna server through my Rockna DAC.
Just as there's a very noticeable difference if I play the same SACD using the Oppo internal DAC or send the DSD stream to the Rockna DAC.
It's like saying that if you play a MOFI or UHQR or other high fidelity vinyl record on a $300 turntable with a built in phono stage, that it's going to sound better than a "standard" pressing of the same record on a $5000 turntable with a $5000 cartridge and a high quality phono stage.
It's very easy to demonstrate and the type of music doesn't matter.