solderdude
Grand Contributor
so even if the output impedance of a DAC is nearly 0 ohm, there would be no difference to the same DAC design was with 500 ohms of output impedance
Yes, but DAC output resistances will not be near 0 ohm, only headphone out and speaker out will be.
To prevent issues with cables etc. the output R of a stand alone DAC (only) will usually be higher, in the order between 50 and 100 ohm or so..
In the thread the 'DAC mode' simply is volume at max. In principle it has nothing to do with output R of the device but everything with an 'assured' high load resistance.