Mikescotland OK, I understand what you're saying. I've been doing car audio for a while now. And for every Pioneer, Kenwood and Alpine I specified the running time in cm in a menu like that and it always worked with fine adjustment. But the bass was never less intense when inputting in centimeters. Yes, the soundstage shifted, that's true. But the bass was always the same intensity. Not with the Dudu. It's hard to describe. But sometimes the bass is strong, and sometimes it's as if it's coming from below. Or as if you're holding some kind of bass reflex tube. Just as an example.
If the function that Dudu offers is not intended for that purpose, then it shouldn't be offered at all.
And if I use the other menu as you suggested, the passenger becomes much quieter. Like a kind of balance. But that has nothing to do with an LZK. Although it says driver and passenger.
