I am giving a try at AudioNirvana, it's ok, I am not sure I'd buy it, way weird the way it handles the music, with iTunes the advantage would only be to easier create playlists whilst on this you gotta go through the hassle of doing it manually, besides that the output quality is supposedly much better with tons of settings whilst iTunes is not, I seem to understand, oriented to audiophiles.
There is VOX which was a nice alternative until they decided that to be able to use the equalizer you have to create an account and I am sick of having accounts even with the grocery store...
Never heard of Clementine but, so far, it seems like an abandon project dating back to 2016, gonna give Nightingale a try but seems very much like the others as far as the ability to create and handle playlists
Grazie