miniDSP has a whole range of products especially for you. :)
In addition, Roon has DSP built in, and configured per output device.
Can you use an EQ program with a streamer?
I listen to digital files - WAV files mostly - from external hard drives via a PC. I would gladly seek the superior sound quality of a streamer, but for the fact that I exclusively listen through my collection of headphones, for each of which I have a different customized EQ setting. I've tried, and no un-EQ'd headphones give satisfactory results to my taste...and these are some of the best 'phones around. I also need to skew the channel balance to the left for the image to sound balanced to me - which is an artifact of my sense of hearing, not of any of my hardware or software. To facilitate all of this, I need an EQ program loaded on my PC (I use the so-called "Peace EQ" for this). I realize this is probably not ideal for sound quality, but I just could not enjoy music with my headphones without a graphic EQ and balance control. Is this at all possible with a streamer?
To complicate matters, I also listen to CDs from an external USB CD drive plugged into the PC. Any suggestions would be appreciated...or am I just stuck with what I have now?