I agree with bigkdz. If you can’t tell which one is better within the first 30 seconds there really isn’t a significant difference.
What????? Jesus. What exact test tones are you using? It takes several tracks just to fully exercise a DAC. Bass, air, imaging, impact which is not to mention some issues like fatigue, take much longer than 30 seconds to set in. Then how will you compare the Redbook, High Rez and DSD performance? 30 seconds is barely long enough to eliminate a DAC you will never like, assuming it is warmed up but is not a fair way to choose among good performers, unless you believe they all sound the same, and specs are all that matter. If this is you, buy the cheapest you can find.
Best,
E