FabFilter User Forum
FabFilter Pro Q3 as crossover in active system
Hi,
If I was to use Fabfilter Pro Q3 to create crossover filters for an active system, would there be any timing/latency issues when the signal recombines at the crossover frrquencies?
Dynamic Phase setting supposedly yields zero latency. Would this 100% zero latency or is there some very small (negligable) latency?
For a simple example - in a 2-way active system, you'd run 2 instances of Fabfilter Pro Q3 in parallel. One instance would have the low-pass filtering and the other instance would have the high-pass filtering. The outputs will go through the soundcard outs to amps to the speaker drivers. When the speaker drivers output their respective low-pass and high-pass bands - will they be in sync or will there be potential timing issues?
Thanks
At least in my system all instances of Q3 in Natural phase (I think that's what you mean) show the same 7.3 ms latency, regardless of the filter(s) in each instance, so there shouldn't be any timing problems. If you want zero latency, well, use Zero latency... For something as simple as a crossover filter I doubt it will make much of a difference.
BTW, maybe you already know this but don't forget the sqrt(2) scaling of Q in Q3, so if you want to implement e.g. 4th-order Linkwitz-Riley crossovers, set the Q at 0.707 instead of 0.5.
Cheers,
Hi Cabirio - thanks for the info. And no - I haven't purchased Q3 yet. So, I didn't know about the Q factor scaling issue. Thanks for the heads up.
7.3 ms is pretty good. I don't get how they keep the latency static regardless of processing load - unless they know what the latency is for a worst case scenario and use that latency regardless of the settings.
a Question that I have always had is - how to they design a plugin with zero latency? I mean - even minimal processing must take some time.
Thanks,
Steve