Q values greater than 10

[L0ki]

Is there any chance that we could get support for q values larger than 10 in the equalizer? Also, support for a larger preamp range that goes beyond + 6 and -12 dB? 

[maxmp]

@L0ki preamp is going to be increased in the next builds, as for Q factor, what are the use case of such high number? It may create highly resonant filters and also it reduces ease of use for the "normal" range.

[L0ki]

Really just to create very narrow peak filters. You could change it so that you could put in manual values that are allowed to go higher without affecting the dials. Is there a downside to widening the range on both? I get that it's mostly an edge case but I have one pair of headphones where I would normally preamp at -13.4db which puts them just outside of the current range. If there was a super sharp cut in the starting frequency curve and the only way to target that was using an incredibly high q value isn't that what I would want to do? Otherwise I would be affecting the neighboring frequencies.

I'm definitely not an expert on this so if you have more suggested reading on the topic of high Q values and filter resonance, I'm open to learning more.

[maxmp]

@L0ki https://en.wikipedia.org/wiki/Q_factor. By the way, why not to use Peak filters, they are quite steep by design? Poweramp (player) uses biquads as filters (2nd order filters) where you can't get that extremely steep roll-off. Some extreme values may auto-generate signal instead of filtering if parameters go way off. 

Still I added options to change some equalizer max/min values into TODO. Thanks!

[L0ki]

1 hour ago, maxmp said:

@L0ki https://en.wikipedia.org/wiki/Q_factor. By the way, why not to use Peak filters, they are quite steep by design? Poweramp (player) uses biquads as filters (2nd order filters) where you can't get that extremely steep roll-off. Some extreme values may auto-generate signal instead of filtering if parameters go way off. 

Still I added options to change some equalizer max/min values into TODO. Thanks!

Cheers! Would you say that making small corrections with high Q values is more counterproductive than just leaving small 400hz width treble 2-3db inaccuracies alone? I know generally the prevailing wisdom is that lower Q values are better whenever possible so I may well have been over correcting.

[MotleyG]

19 minutes ago, L0ki said:

Cheers! Would you say that making small corrections with high Q values is more counterproductive than just leaving small 400hz width treble 2-3db inaccuracies alone? I know generally the prevailing wisdom is that lower Q values are better whenever possible so I may well have been over correcting.

In my experience less is often more when it comes to EQ functions. I would try to use less bands in most cases, addressing only the areas that need attention for your specific function. A factor of 10 or greater is just a very thin slice, highly unlikely an audible change without significant boost or cut. And using multiple high Q bands close together will create more noise and issues than one single low Q band.

A traditional 1/3 octave graphic EQ features 31 bands. However when using parametric equalization often 7 bands or less can accomplish similar results.