i was able to get analog audio from the orange pi one (with some soldering of course) and its plugged into my speakers, but the sound quality is poor while using the default mpv player that came with the image. Were is the equalizer so i can change things like frequencies to make more bass or treble? The music sounds flat like from a portable dvd player.

Did you ever get a solution for this? I made some bass reflex boxes for my odroid boom bonnet but I'd still like some equalization.  Debian has package pulseaudio-equalizer but I have not found it yet for arm.