A DAC, or digital-to-analog converter, is required to deliver audio signals to your 3.5mm headphones, regardless of whether your smartphone does or doesn’t have a dedicated 3.5mm headphone jack. Therefore, this conversion can take place either on the smartphone itself – this is always the case for phones equipped with a 3.5mm port – or on the USB-C dongle. In the case of the Galaxy Note 10, it seems like the digital-to-analog conversion for 3.5mm headphones might be handled by the optional USB-C dongle itself. The product description states that it “provides ultra high-quality audio by converting digital files to analog,” therefore it’s pretty clear that the Note 10 optional dongle does incorporate a DAC. EE-UC10JUWEGUS USB-C Headphone Jack Adapter USB Type-C to 3.5mm Headphone Jack Adapter Provides Ultra High Quality Audio by converting digital files to analog (up to 24bit/192kHz).   $ 14.99 ... View more