FabFilter User Forum
Potential Issue with Collision Detection in Pro-Q 4
Description:
I am using two channels, each with an instance of FabFilter Pro-Q 4. On one channel, I applied a low-cut filter to remove low frequencies to address frequency collisions with the other channel. After making this adjustment, I noticed that the red collision marker in the analyzer becomes less intense but does not completely disappear.
Expected Behavior: I expected the collision marker to disappear entirely once the conflicting frequencies were adequately reduced or eliminated.
Question/Concern: Is this the intended behavior of the collision detection feature? Should the red marker persist in some form even after the frequencies are cut, or should it fully disappear once the collision is resolved?
Shay Peleg — Jan 11, 2025
Hi Shay,
We designed the collision spectrum merely as a reference for potentially problematic areas. However it will never disappear completely it merely shows which frequencies have the most overlap. In the end you're going to have to be the judge.
I'm also having problems with the collision. I know in the end my ears are the judge, but a visual cue is still helpful for workflow. But it's acting strange, I'm using reaper. Sometimes it shows collision in a track by itself that isn't set to be analyzing any other tracks or have anything side chained to it. Like just by itself in isolation it's showing that it's masking... Itself basically? Is this normal? Or maybe reaper is doing something weird with the routing? Or is it suggesting that there's an excess frequency build up in that area? I didn't think that was something this was supposed to do, but it's showing collision on a track that's supposed to be in isolation.
I have the same issue when I add Pro Q to 2 tracks: one completely silent, another generating sound. The red glow still shows up, even though the other track is completely silent.