I am finally seeking advice on some digital matters. I currently have 2 vintage systems set up in my house. One is all vintage 2 channel component system with a Marantz 2270 as the hub for sound. The other is the same type setup just in another room and it's hub is a Sansui 8080DB. There is a computer in both these systems the Marantz system has a Dell desktop and the Sansui system has a modest SFF Lenovo. I use the computers in both these systems in much the same way. Streaming music from Tidal and other digital streaming sources. In an effort to improve on the sound of both systems I added an external sound card to them. I already had a Creative Sound Blaster X-Fi Surround 5.1 Pro Sound card that at one time was connected to a surround channel receiver that was in the system (prior to the Marantz's arrival). The Sound Blaster's sound was really good and much better than the built in sound card so I was impressed. I was impressed enough that I ended up with the same card in the other (Sansui) system too. Of course they are both running in 2 channel mode now no 5.1 going on. Now my question....Is this sound card doing as good a job as a good DAC would be? The sound card has an optical out and an analog out as well as an analog input. I listen to Tidal a lot and their MASTER tracks that are Hi Res do sound good with the cards. The Sound Blasters claim that they handle up to 24bit 96khz. so I have just been wondering. Am I getting a fair benefit from these sound cards or would a DAC be better? Being unfamiliar with the differences between a sound card and a DAC maybe someone could explain those differences and an opinion on any improvements I could make. I know that a Sound card has a DAC also but what if anything does it do that a DAC doesn't or vice versus? Thanks for the help!