doing an uber loud master today (not by choice …), and on the loudness display tab of audio files, I can’t get the reference and lowest loudness control go above -10 dB LUFS (see attached screenshot)
I seem to recall I was able to before …
Because that has non-sense to go above -10 dB. Actually, -10 dB is already non-sense.
If somebody is requesting you this, my guess is that he speaks about another scale.
Actually, it really depends on the harmonic content (since LUFS are frequency ponderated) and type of arrangements. In some genres of “tighly-packed-allways-full-power” electronic music, seen from the markets demands (i.e. artists and DJs), -10 LUFS is on the quiet side, you have to convince very hard to not go louder. Doesn’t work each time.
Anyway, not really wanting to get into the do or don’t, I would still prefer to be the one to judge the client, not my software