My 32 cents on DSP:
- Digital signal processing almost universally affects sound quality (SQ). Sometimes good, sometimes bad. Performance is almost always dependent on your specific setup; headphones, amp, DAC, etc. As such, it is nearly impossible to give a blanket recommendation for or against DSP.
- Implementation is everything. Convolution filters, parametric EQ, and pretty much everything else that messes with audio signals in the digital domain, tend to heavily influence SQ in one way or another. if you end up getting serious about using DSP, there are hardware considerations as well.
- I've personally had the best luck using HQPlayer. Roon's newer "Muse" DSP engine is a significant upgrade over the previous version, but still falls short of HQPlayer. As always, your mileage may vary. I can provide more details if you're interested.
- The only opinion that truly matters is yours and there is just no substitute for your ears with your system. You have to try different combinations and see for yourself. If you find something you enjoy, keep using it and don't ever let anyone talk you out of it.
- Record your configurations! I can't tell you how many times I've been three (+) whiskeys deep messing with settings and accidentally tripped over a great configuration...only to forget how I did it the next day. Probably not an issue for most, but I'm a degenerate, so there's that.
Hope this helps.
- lj
Edit: if you plan on tumbling down this rabbit hole, be particularly mindful of hardware limitations/requirements. In its purest form, HQPlayer is basically a Chord Mscaler on crack with (potentially) higher hardware requirements to match.