1 Series, 3 Series, 5 Series and so on. The speaker and tweeter fit 75.20mm into the factory location and use the factory connectors, you will enjoy the strongly improved sound quality with the help of the B2 audio sound upgrade system. 49.60mm 25.60mm...
4. Next replace the tweeter and re-insert the foam to the triangle housing. The below illustration shows that the tweeter is flushed perfectly into the door triangle housing (door triangle housing is not included in the B2 audio Plug & Play component kit, you can order the triangle part from your BMW dealer, as you can see it has the speaker grill and holder for a tweeter where the standard doesn't.)
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Installation 7. The below illustration shows the comparison of factory speaker(left) and B2 audio upgrade 4” speaker, B2 audio mid-range speaker uses a cast aluminum chassis, powerful yet tiny neodymium magnet. 8. Replace the original mid-range speaker with B2 audio mid-range speaker, using the original bolts.