http://www.techradar.com/news/the-lg-v30-is-getting-advanced-hi-fi-quad-dac-audio-features

One of the things that fans of LG's V series have come to expect is next-level audio in their smartphones. The LG V20 featured a 32-bit Hi-Fi Quad DAC (Digital-to-Analog Converter) which essentially converts your digital music into an analogue signal, allowing it to be amplified by speakers and headphones without succumbing to digital distortion. 

In layman's terms, it made music sound fuller and more robust, bringing it closer to how the original source would've sounded. If you're one of the people who has heard this kind of enhanced audio output, you know what a night and day difference it can have on your favourite music.