FabFilter User Forum
Ceiling value
I have read nearly all the forums, but my question still exists. there is no way to set the ceiling value other than 0db. In one of the forums, it said that the output value acts as the ceiling and then you can add limiting by increasing the gain but for example, I want to set the ceiling at -3db and I set the output at -3 the volume of the audio goes down by 3db, then I have to add gain of about 3 dbs to make it at the same level thus it gets very hard to dial in the right amount. instead it should be just cutting the peaks above -3, and in case I want to increase loudness I can increase the gain. Please help me out, thank you!
Detox — May 19, 2022
Hi! I think I've just replied to your email as well, correct?
Pro-L 2 works a little bit differently than most other limiters. It does not have a ceiling or a threshold. Basically Pro-L 2 always has a ceiling of 0dBFS, or 0dBTP if true peak limiting is enabled. Nothing will pass this 0dBFS. With the gain slider you can push your material into the limiter. The output knob is basically just a post-limiter attenuator. If you do not want your audio to peak above -3dBFS you should set your output to -3dB. However, if you do not compensate the input, this will indeed reduce the loudness of all your signal. In order to keep the same loudness, you would have to compensate by adding 3dB of gain on the gain slider as well. This way you keep the same loudness but it will never peak -3dBFS.
When you are holding the Alt button (Shift in Pro Tools) while adjusting the gain slider or output knob, Pro-L 2 will automatically level match the input and output. So when you hold the Alt button and push up the gain slider to +3dB, the output will automatically go to -3dB. Same goes for then you adjust the output knob, the gain slider will be compensated.
When there is no limiting applied, so when there is no gain reduction, a signal that is gained by +3dB and reduced by -3dB on the output knob will sound exactly the same as the signal without Pro-L 2 inserted, or as a signal with Pro-L 2 set to +6dB and -6dB. If the input gain and output level are perfectly matched you should get a complete null during a null test, except for the parts where the limiter is actually limiting.