BMW 328is Speaker Size

Front Door Panel Speaker

Front Kick Panel Speaker

Rear Deck Lid Speaker

Rear Door Panel Speaker

BMW 328is Speaker FAQ

Which speakers should I replace first in my BMW 328is for the biggest sound improvement?

Replace the front door speakers first - they handle most of your music's detail and vocal clarity. For 1997-1999 BMW 328is models, you're looking at 6x8 inch speakers that can be coaxial, component, or full-range types. These front door speakers typically handle 40-60 watts RMS and work with 4-ohm impedance. The front doors produce roughly 70% of what you actually hear while driving. Component speakers will give you the cleanest separation between highs and mids, but quality coaxials around 50 watts RMS might be enough depending on your listening habits. Check if your current speakers are producing muddy bass around 80-120 Hz - that's usually the first sign they need replacement.

Can I use component speakers in all locations of my BMW 328is?

Component speakers work best in the front positions where you have space for separate tweeters and woofers. Your BMW 328is front doors (6x8 inch) and kick panels (5.25 inch) can handle component setups effectively. The rear deck lid speakers are typically 4 inch full-range only - not enough space for component separation there. Component systems need crossovers, usually around 2500-3500 Hz cutoff points. Front kick panel components at 5.25 inch can complement your door speakers, but verify your head unit can power both sets properly. Most aftermarket components need 25-75 watts RMS per channel. The 1996 models had different front door sizing at 5.25 inch, so component options vary by year.

What's the difference between coaxial and full-range speakers for my BMW 328is?

Coaxial speakers have a tweeter mounted directly on the woofer cone - you get highs and mids from one unit. Full-range speakers attempt to reproduce all frequencies through a single driver without a separate tweeter. Coaxials typically perform better above 3000 Hz because of that dedicated tweeter. For your BMW 328is rear positions, 4 inch coaxials will give you clearer highs than full-range equivalents. The frequency response difference becomes noticeable around 4000-8000 Hz where full-range speakers often start rolling off. Your front 6x8 speakers can benefit from coaxial design since they need to reproduce everything from around 80 Hz to 15000 Hz effectively. Full-range might work fine for rear fill, but coaxials generally offer better balance across the spectrum.