I've been researching this all over this forum, this seems to be one of those subjects that give vague results on searching.
I got:
-HiFi system - E90 US Spec
-BSW Stage I Speaker Upgrade (
link)
I want to upgrade the amp.
When I search for plug-and-play amps here, I read very mixed reviews. I want to do a pnp amp that gives me strong highs and mids. I don't want thumping bass.