1. USB-C to 3.5mm adapter with DAC (Digital-to-Analog Converter): This type of adapter contains a built-in DAC, which converts the digital audio signal from the USB-C port to an analog signal that can be sent to the 3.5mm audio jack. This is similar to the traditional headphone jack found in devices prior to the adoption of USB-C. The DAC ensures that the audio signal is properly processed before being outputted to your headphones or speakers. This type of adapter is used when a device lacks a dedicated audio jack, such as some smartphones or laptops, which only have USB-C ports.
2. USB-C to 3.5mm adapter without DAC: Some devices, like your computer with the Realtek ALC897 chip, already have a dedicated audio chipset onboard. In this case, the USB-C to 3.5mm adapter does not need to include a built-in DAC. Instead, the USB-C port is designed to carry analog audio signals directly, using certain pins (SBU1 and SBU2) in the USB-C connector. This type of adapter simply acts as a physical connector, allowing you to connect your 3.5mm headphones to the USB-C port of your device for audio output.
