I like using iTunes' equalizer, but that only works in iTunes.
I'm looking for some software that lets me apply a global, system-wide equalizer to Mac OS X.
The app (or pref pane, etc.) would let me change EQ settings and have that apply to all apps (iTunes, Spotify, Chrome, etc.).
Ideally the software would have some nice presets like iTunes does.
Free preferred, but I'm certainly willing to consider buying something.