Originally Posted by visia
I don't think there is a universal rule of thumb. You have to look for a specific combination. There are few threads that D1 is much better as DAC-AMP, compared to standalone AMP. H120 is the only mp3p which has optical out that I know off and D1 is the only portable DAC/AMP which has optical in, so it may be the only option for such a combo. That said, there are amps exceeding D1 and sources better than H120, which are better SQ wise. For example, iMod/GS Voayger using analog connection to me is cleary better than H120/D1 combo using digital.
Thanks for the response.
I'll rephrase: is the (analog) line out, of say, an ipod vastly inferior to the sound of a digital source plus a DAC assuming the same headphones and file types (MP3)?