I did a little bit of searching trying to get an idea of what upgrades were available for the F80/F82/F83 and wanted to make a short list of some of the options. For those who don't know, the options available depend on which stereo you've got as there are three main configurations, here are the descriptions courtesy the Bavsound website:
Base (Stereo)
Standard (Hi-Fi)
Harmon Kardon / Premium (Top Hi-Fi)
Bavsound:
Revenant Amp drop in replacement for all Hi-Fi cars:
Ghost Underseat subwoofer - All cars - (4 and 8 Ohm):
Stage one speaker Upgrade:
Sedan | Coupe | Convertible - Top Hi-Fi
Sedan | Coupe Hi-Fi
Base (Stereo)
This is BMW's most basic audio system offering. Available ONLY outside the U.S. except for 2010 and some 2011 model year BMWs when it was offered in the U.S. There are no factory tweeters present in the pods behind the side mirrors....
If you live in the U.S. and have any model year BMW besides 2010 or 2011, you most likely do not have this audio system. If you live outside the U.S., this is the audio system which comes standard on most BMWs.
Specifics vary by vehicle, but this audio system is generally characterized by a lack of an external amplifier, and usually just 6 total speakers (often without tweeters), and generally very poor overall performance.
Standard (Hi-Fi)
This is the "standard" audio system offered in BMWs in the U.S. (except model years 2010 and 2011 when "Base" was standard equipment) and an optional upgrade for BMWs outside the U.S. ...
If you live in the U.S. and do not have one of BMW's "Premium" audio system offerings or a 2010 or 2011 model year BMW, you have this audio system.
Although exact specifics vary from vehicle to vehicle, this audio system is generally characterized by 10 total speakers and an external amplifier, no user adjustable "DSP" processing or equalizer settings, and "average" overall performance.
Harmon Kardon / Premium (Top Hi-Fi)
The is the premium audio system type for a large number of BMW vehicle years and models, typically characterized by a more powerful amplifier and more total number of speakers. Look for logos that say "harman / kardon" on your speaker / tweeter grilles. If you see that logo, you have the "harman / kardon" system.
Bavsound:
Revenant Amp drop in replacement for all Hi-Fi cars:
Ghost Underseat subwoofer - All cars - (4 and 8 Ohm):
Stage one speaker Upgrade:
Sedan | Coupe | Convertible - Top Hi-Fi
Sedan | Coupe Hi-Fi