Although I was limiting on the basis of the True peak (intersample peak) in the recent update of AI Mastering, there are cases where it is desirable to limit on the basis of ordinary peaks depending on the application.
I added the "Ceiling" option for that to the "Custom Mastering" of AI Mastering.
Specify the maximum output level. It is the same as Ceiling of the general limiter VST plug-in. 0 dBFS is the maximum. If encoding is required in later processing, it is possible to prevent clipping due to encoding by making it a little smaller value.
"Ceiling mode" option
Specify the reference calculation method of the maximum output level. It is the same as the oversampling option and True Peak (intersample peak) option of the general limiter VST plug-in.
Peak is the so-called normal peak and is based on the maximum value of the amplitude of the discrete waveform.
True Peak is an intersampled peak with reference to the maximum value of the amplitude after converting discrete waveforms into continuous waveforms.
True Peak (15 kHz Lowpass)
True Peak (15 kHz Lowpass) is based on the intersample peak after low-pass filtering at 15 kHz. You can simulate the peak change due to YouTube's re-encoding, so it's best for making sounds for YouTube.
How to make it operate like a conventional one?
By setting as follows, the same operation as before can be done.
"Ceiling": 0 dBFS
"Ceiling mode": "Peak"