What is the best "Q" Setting for audio mastering?

[Trythanks Lightfoot]

Perhaps my question is kinda broad but in most given situations what would y'all recommend as an ideal quality factor (or bandwidth) for audio mastering?

 

[AwardReady]

@Mpumelelo von Mumhanzi I recently watched this Hot Trax Production Magazine video on YouTube where Chris Athens was talking about using a narrow bandwidth at around 100 Hz and a medium bandwidth at 8 kHz.

What would you say corresponds to a narrow or medium Q i.e., when using a VST plugin. By the way what equalizer was Chris Athens using?

This:

Hardware Sontec Q 6 = 1 (on most digital EQ plugins)
Hardware Sontec Q 9 = 2 (on most digital EQ plugins)

For FabFilter EQ that will be Q 1.5 and Q 2.5 respectively.

What is an octave on FabFilter Software Instruments Pro-Q?

The title says it all. I am wondering what's the quality factor (bandwidth) to set FabFilter Software Instruments Pro-Q to one octave. Is that Q 1.414 like what most people suggest on YouTube?

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