While the term "9D" is a marketing label rather than a scientific measurement, it represents a specific style of binaural audio engineering. In 9D versions of "Hellevator," the vocals and instrumentals are isolated and panned independently, creating a "ping-pong" effect where sound appears to orbit the listener’s head from multiple directions simultaneously. The 9D Audio Experience

For many fans (Stays), listening to "Hellevator" in 9D provides a new way to connect with the song's lore. The swirling, multidimensional sound mimics the feeling of being trapped in the "maze" described in the lyrics before the powerful chorus "breaks through" the spatial field.

: This effect relies on binaural recording principles to trick the brain into perceiving a 360-degree soundstage. To experience the full depth, headphones are required .

: The title is a portmanteau of "Hell" and "Elevator," symbolizing the grueling journey of a K-pop trainee.