FabFilter User Forum
Ideal Input Level for Pro C
2 part question - first - curious if there is an ideal input level for the Pro C? Secondly, interested to know if it's bad to have overs on the input - seems like a silly question, but i have audio hitting the Pro C with +6db over and it literally sounds fine.
Kyle — Jul 24, 2022
Hi Kyle,
Pro-C 2 does not have a sonic sweetspot. It does not matter how loud a signal will enter the plug-in. The characteristics that each compression style includes are only applied to the compression itself. When no compression is applied, Pro-C 2 will not alter the sound. There are no characteristic effects or harmonic distortion on the input or out put stage of Pro-C 2. So it does not matter if you enter the plug-in hot or not.
Most DAW's currently have a floating bit depth. This means that the bit depth will adjust according to the level of the audio, so that the audio will never clip inside your DAW. You will not hear any clipping if the audio will enter our plug-ins above 0dBFS. However, if your signal enters Pro-C 2 at +6dBFS it might be harder to set the correct amount of compression, as the threshold only goes to 0dBFS. So event though technically it might not be an issue to run our plug-ins hot, it it advisable to maintain healthy gain staging in order to keep control.
If you aim for -18RMS average ( 0 VU ) you should be in good shape.
It's not always about plugin sweet spots, but is equally about the channel fader sweet spots. Since faders are scaled logarithmically, they are much more precise up at the top around 0dB / unity. If you have the fader lowered to -20dB then small movements will be much more coarse and have a larger effect on the signal.
Thus overdriving your plugins and sending a +6dB signal will only result in you having to turn down the channel fader during mix down, making it much less useful for precision volume control. That is one of the reasons why gain staging is so important.
If you're of the "well 32-float means I can ignore peaking indicators" generation... Trust me you're going to be turning down the signal at some point... If you sum together 20+ tracks which are at +6dB then you have a mix / master bus which is peaking at like +20dB. And this isn't something any plugins want.
So just gain stage with a VU meter or target -18RMS like engineers have been doing for decades on analog consoles. Its a pretty cool old school technique and can make your mix sound way more "analog" than crushing an SSL bus compressor emulator / Tape saturation chain with a +6dB signal. And it helps to keep your faders up and thus more usable.