FabFilter User Forum
Pro-L2 adds undesired DC offset to output
Thanks for the detailed report! We'll investigate what's going on.
Cheers,
Frederik (FabFilter) — Mar 24, 2021
We can confirm the slight DC offset and will fix it in the next Pro-L update. Thanks again for the report.
Cheers,
Frederik (FabFilter) — Mar 29, 2021
FabFilter,
I noticed that the Pro-L2 adds some DC offset of its own with some limiter styles. (Note: I did my due diligence, confirming that the DC offset was not coming from the tone generator itself, the DAW itself, etc.)
As an example with analyzing the styles I use most, Modern and Aggressive, I see a significant bump at 0Hz.
The DC offset control setting has no effect, as this DC offset is being added by the Pro-L2 itself.
When I add another Pro-L2 instance after the first, and configure the second instance to use the Safe style, unity gain, and DC offset on, it removes the DC offset added by the first Pro-L2. But I should not have to do that.
Can this be fixed in the next release, please?
Thanks,
Fred
The link is a screenshot of the analyzers:
substrate.com/images/fabfilter_prol2_dcoffset.png
Inputs are 1kHz sine waves at -1dBFS.
The left analyzer shows the output of a Pro-L2 using the Modern style; the right shows a Pro-L2 using Aggressive. Neither is ideal, but note how much more DC offset is generated by Aggressive.
I annotated the screenshot with some arrows pointing to the DC offset bump in the plots.