what is the width of the "q" parameter in Rockbox EQ?

[shady_slim]

Hello,

This is my first post here. Before starting this thread I searched the forum, I have also read carefully the RB manual, but could not find an answer to my question.

I have Sansa Clip+ with RB v. 3.7.1 and Phonak PFEs with green and gray filters.

PFEs are great phones - much better than my previous ones, yet I am not fully happy with either filters: the quantity of bass with the green ones is OK, but the quality - not - they seem to dampen all frequencies but med- and upper bass (including lower bass!) - which is not acceptable for me.
The bass quality with the gray filters is very good to me - it is fast and detailed, also at the very lowest end, but the amount of it is just too low and the higher frequencies are just too overwhelming to me.

Of course - the black filters could be a solution, as their signature is somewhere in between the gray and green ones, however, I chose first to play with EQ settings on my Clip+ to see how satisfactory results can be achieved with it. Then I may buy the black filters just to have comparison of the EQ capabilities and the filters.

Knowing the characteristics of Phonak`s gray filters (the diagram is available on many sites - also here at abi) I would like to make it as linear (or rather sloping a bit down as the frequency goes up) using the advanced/graphical EQ. Actually - I have already done some EQing, but am not sure how accurate it was - just because I do not know how the "q" parameter works at different frequencies...

My guess is the width of the "q" changes with frequency - e.g. q=1 at 100 Hz means 100 Hz +/- 10Hz (so we can @ 100 Hz it is 20 Hz "wide"), while q=1 at 4000 Hz means 4000 Hz +/- 400 Hz (so we can say @ 4 kHz it is 800 Hz wide).

In the example above q=1 width is equal to 20% of the frequency it is applied at both for the frequency of 100 Hz and 4 kHz. So we could say it is a constant ratio parameter. Of course - it is just my assumption - it does not need to be constant and it may be calculated in a totally different way. But even if it is constant - the original question returns - how wide is it?

I will appreciate your help!

[CrowdAds]

[orby]

your basical idea is right, and your concerns about that it probably wont be exactly as you think are reasonable as well.

you should get all information neede here

http://en.wikipedia.org/wiki/Equaliz...#Parametric_EQ
http://en.wikipedia.org/wiki/Q_facto...quality_factor

this is how it should be. dont know if rockbox treats it exactly like this.