I'm not looking for the street thunder effect... just want quality, clear music that you can truly feel and enjoy on long rides...

600 watts on 9 channels on the premium sound system sounds like more than enough...(compared to the 250 watt stock system it comes with)

i think if it still needs a boost a simple upgrade of speakers (same size) will make a difference...

plus you do get an extra 4 speakers in the rear... i'm sure that helps circulate the sound too!

i think i'll go with the premium upgrade... (don't like the idea of doing boxes in the rear... ) i want to keep it looking stock...

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2012 X5 50i M-Sport
2014 X3 35i M-Sport