FabFilter User Forum
Output Clipping
Hello,
I am using Pro-Q to crossover my stereo speakers to my subwoofer.
So I send the audio signal with a High Cut to the subwoofer and another copy of the original signal with a Low Cut to the speakers.
However I have noticed that the plugin with the Low Cut clips. I am using the Low Cut with a 24dB/oct slope.
According to the manual, Pro-Q actually doesn't clip and it should be fine to send its processed audio to the speakers like that, since it's the only step in the chain.
Am I correct about this?
Also just out of curiosity, I'd like to know why it clips in the first place, even though in theory I'm removing and not adding.
Thank you.
DJNX — Nov 23, 2020
Hi DJNX,
When plug-ins are using floating point processing internally, they indeed cannot clip theoretically. However, the meter of Pro-Q does visualise the output metering in full scale with a max of 0dBFS. So even if the sound in the plug-in does not clip when you go over 0dBFS, the meter will still clip to indicate that you need to keep an eye on your gain staging.
When using filters you indeed remove signal, but almost all filters have a small resonance frequency. With high pass filter this results in a tiny boost just above the cut-off frequency before you start decreasing the signal. This small resonance could cause clipping of the signal.
Cheers,