Thanks for the research ;-)
It's not that I am aiming for a meter that is scientifically correct. (makes no sense for this purpose)
My main objective is that the needle moves nicely for different sorts of music and volumes.
The experience should be nice.
It was a bit of a challenge to get smooth movements at the very bottom and the top, but I am almost there.
The reason for my question was that it is a bit misleading that where my meter says -50 dB, it is actually around -20 dB.
Or where it says 0 dB, it is actually around +3 dB.
Somebody recently told me there should be at least some truth in advertising…
But I think I found an acceptable solution. I will leave both the horizontal black and red scale, and the percentage indicators just as they are, and will only change the dB values.
It's probably going to be this:
It might prevent some complaints from people that are used to and/or trained to look at VU meters ;-)