Hi mwillems. I'm hoping you might be able to help me with a starting point for PEQ for my particular hearing loss pattern. I've attached the relevant part of my hearing test. Thanks for any pointers!
It looks like your left and right ear are a little bit different so I'm going to offer a "blended" suggestion to try and split the difference. I'd suggest starting with the following filter shapes:
1. A high shelf with the frequency set to 2000Hz, the Q set to .8, and the gain at +3dB.
2. Next, a high shelf with the frequency set to 3000Hz, a Q of 1, and the gain on this one at +5dB.
3. Then, a high shelf at 3500Hz with a Q of 1, and a gain of +3dB
4. Finally, an "adjust the volume" filter with a -11dB setting.
Once you've dialed those in, you should put on some familiar music and tinker with the settings to suit your taste. The first step I'd suggest is increasing or decreasing the gain of the filters (but leaving the Q and frequencies alone just at first). If you decide you want to branch out into additional tinkering, here's an explanation of the filters and parameters to help you in tailoring them:
A high shelf with a positive gain looks something like the blue trace in this image:
http://en.wikipedia.org/wiki/File:Shelving-eq.svgYou can see that the shelf in the illustration increases the volume of frequencies above a certain point, and it rises for a while and then stops.
The frequency setting determines where the center of the rise is. The high shelf in the link probably has a center frequency of around 4,000Hz, give or take.
Q determines how quickly the shelf reaches its top (higher Q is faster, lower Q is slower). The shelf in the link has a Q of around .5. FYI JRiver doesn't support shelves with steeper Q's than 1 (higher values can be entered, but are ignored). That's one reason I recommended several shelving filters (more on this below).
The gain setting determines how much rise the shelf will have total. The shelf in the linked picture has a gain of 9dB.
With that said, you can probably see why I recommended a few shelving filters. Your chart at the macro level looks kind of like a high shelf filter in reverse (or a high shelf with negative gain). I recommended staggering a few shelves because your chart shows a gradual dip followed by a steeper slope; staggering a few shelves creates a steepening effect.
The total gain the shelves apply is about 11dB, which is less than the total attenuation in your chart (between -15dB and -20dB from the baseline depending on the ear). I suggested starting with less gain because my experience has been that its best to start with less boost than you think you might need. You can always add more (or less if need be).
One important note on the 4th suggested filter: it's there to offset the total gain added by the shelves. That step is important, or you might wind up driving your audio output into clipping. If you're trying out different settings and increase the total gain of the shelves, you need to lower the volume to offset the new gain.
Hopefully that will get you started in the right direction. Please let me know if that helps at all, or if you have any questions.
Is there any hope that MC will ever allow these sort of plugins on streaming output? It strikes me that it could be possible during a transcode to PCM or something similar.
There's been talk of applying DSP to DLNA output, but the general consensus so far has been "not soon."
In the current toolset, if you're the only one whose going to be listening to the media you can potentially use the convert format or handheld sync tools to "bake in" EQ, but if you decide to go down that road be sure to keep a back up of the original file!