Instead of it being just another electronic DSP control (like ANC strength or bass boost), my guess is that it’s a physical/mechanical slider built into the headphone’s structure.
Here’s what I mean:
The slider might adjust the seal and suction of the earcups.
Sliding it one way could tighten the fit, creating a stronger seal, more passive isolation, and deeper bass.
Sliding it the other way could loosen the seal, letting in a bit more air and ambient sound, giving a lighter feel and more natural listening.
In other words, rather than changing sound through software, it could give a direct physical control over how “open” or “closed” the headphones feel — a tactile alternative to just toggling ANC.
