Blizzard ...
So, there's a way to take the PEQ settings from Fab Filter Pro and convert those to a convolution file with the appropriate sampling frequency and bit depth for HQ Player to process it?
I've tried convolution engines such as Acourate and AudioLens, and while powerful, they did "too much" and sucked a bit of the life out of my system. Fab Filter Pro works a lot better for me.
It's not obvious that VST plugins have to degrade quality. Sure, some are lousy, but not all of them are. Just as with most audio products. It should be entirely possible do the noise shaping and upsampling that HQPlayer excels at following the application of a plug in or convolution engine.
Try REW. It may not be obvious that VST plugins degrade quality. But depends on the quality in the first place. It's obvious to me the difference going from Jriver to HQplayer makes. Jussi knows how the code works, and he didn't find the way VST plugin's work to be acceptable to achieve the level of quality acceptable for HQplayer. Otherwise, he would make them compatible. It's not because he doesn't know how to do it.
What would be nice is if fabfilter allowed export of impulse response profiles. I like Fabfilter as well, but I don't like the sound quality, and lack of DSD support bottleneck.