USB vs Digital/Optical

[Doodski]

My Asus is the MB. It is the h170 pro gaming.
The sound card is the Soundblaster Z

I see it now. OOps. Sorry about that. Too many distractions. Now I have to go back and read it again

 

[Mike B]

Your conditions of test included:
1) Original onboard soundcard with 3.5mm cable to the speakers
2) ASUS soundcard with 3.5mm cable to the speakers
3) ASUS soundcard with optical digital to the speakers

If 1 and 2 are compared then one of them will have more output and sound slightly louder. That louder one will almost always be the winner.
When 3 is compared to 1 and 2 there will again be a level mismatch and one will be louder.
To solve this you need to level match with a sine wave, volts meter or decibels meter or oscilloscope and then make them all equal and do it blind.

You all are giving me too much credit. I was not flipping a switch and doing an A/B comparison. I listened using option 1 for a while and eventually ordered the soundcard to see if it would make things better. I installed the soundcard and used option 2 and decided, "This is much better." I then got an optical cable and installed it and listened (always to several of the same songs.) Option 3 sounded different and maybe better than option 2. But I always had to walk to the back of my desk and physically switch a cable. Eventually I ran a USB cable to the speakers and said, "I cannot hear a difference versus the optical cable." So loudness wasn't probably a factor, I had to adjust volume from song to song anyway. Not a lot of science, just my listening pleasure. I'm currently using the USB but I may go back to optical and see if I can detect subtle differences.

 

[TechEnthusiast]

You all are giving me too much credit. I was not flipping a switch and doing an A/B comparison. I listened using option 1 for a while and eventually ordered the soundcard to see if it would make things better. I installed the soundcard and used option 2 and decided, "This is much better." I then got an optical cable and installed it and listened (always to several of the same songs.) Option 3 sounded different and maybe better than option 2. But I always had to walk to the back of my desk and physically switch a cable. Eventually I ran a USB cable to the speakers and said, "I cannot hear a difference versus the optical cable." So loudness wasn't probably a factor, I had to adjust volume from song to song anyway. Not a lot of science, just my listening pleasure. I'm currently using the USB but I may go back to optical and see if I can detect subtle differences.

Isn't it funny though when comparing using a/b method how it gets closer the more you do it. I have been experimenting with this with different amps/dacs and sound cards, and have come to the conclusion that unless they could somehow be played at the same time I could not hear much of a difference. Even Subtle differences disappear after a while. This goes for dac filters as well. Unless it is fuller or louder it is extremely hard to tell. I even found by mistake that the usb sounded great because I thought it was on optical. I believe that our ears adjust over time. That's why other than actual measurable findings such as Amir's benchtop measurements it is almost impossible to discern amongst various equipment. We all are different and hear differently so I will just follow "My" ears backed by acceptable measurements.