Headphone plug USB head and round head

First of all, ordinary 3.5mm headphones are just a speaker, which converts the analog audio signal output from the audio source device into a sound signal sent to the ear; while the headphones with USB interface (except the kind of headphones with Mini USB port on the old cell phone) have a sound card inside, the audio source device will transmit the digital audio data to the headphone's sound card via USB, and then the headphone's sound card will convert it to an analog audio signal, which is then played through the speakers. So, structurally, with the same quality of speakers, the cost of USB headphones is definitely higher than 3.5mm plug headphones, and it's only natural that the price is expensive.

Digital devices to play audio, there must be a DAC process, the digital signal is converted to analog signals (sound is analog), in the computer, the completion of the audio DAC this process of equipment is the sound card. So, whether you are using 3.5mm headphones, or USB headphones, or connecting audio equipment, you must use the sound card, not that 3.5mm headphones do not use the sound card, which uses the computer's internal sound card (generally on-board sound card). USB sound card and the performance of the on-board sound card and who is good and who is bad, I have not done experiments and is not clear, my personal opinion, half-loaded sound card directly from the motherboard I personally believe that a half-loaded card is powered directly from the motherboard, using the motherboard's internal data bus, and its performance should be better than an external sound card (personal opinion, no data support).