I have a headset that supports bluetooth and 3.5 jack. To my surprise the audio quality is better when using bluetooth and poor when using wire to the same source. I have also tried using USB-C cable but still bluetooth sounded better. By sound better I mean the audio is more louder and richer. How is it wireless blueooth offers superior quality than wired connection? Can this be expected?
this is the correct answer, your bluetooth probably has a better amp/dac circuit than your phone does. a dongle would be a better comparison point than straight to the phone.
Trying to make dongle comparison with headphones is solid point.