Start with an Android phone with sufficient storage capability and a
decent DAC/headphone amplifier. Built-in is great; otherwise, find
something that works and doesn’t suck up too much power.
Add IEMs of choice, for less than $50, or cans that are reasonably
efficient. It stops being so portable if you have 800g cans and a 500g
battery-powered amp to drive them.
Install F-Droid, and use that to install Vanilla Music and
RootlessJamesDSP.
Configure Vanilla Music to point to your music data.
Use ADB to enable RootlessJamesDSP (it needs 2-3 android system
permissions).
Download convolution equalization for your IEMs or cans.
https://autoeq.app is an acceptable and very convenient source. If
Oratory1990 covers your equipment (
https://old.reddit.com/r/oratory1990/wiki/index/list_of_presets ) then
choose that, first.
Apply in RootlessJamesDSP.
Enjoy.
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