BMW 840Ci Speaker Size

Front Door Panel Speaker

Rear Door Panel Speaker

BMW 840Ci Speaker FAQ

Should I replace front or rear speakers first in my BMW 840Ci?

Replace the front door panel speakers first. Your BMW 840Ci uses 5.25-inch speakers in both positions, but front speakers handle about 70% of your music's frequency range. The front location also gives you better stereo imaging since you're sitting closer to them. Rear speakers mostly fill in ambient sound and bass response. If you're planning component speakers, definitely start with the fronts - the separation between tweeter and woofer will make the biggest difference up front where you can actually hear the staging.

Can I mix coaxial and component speakers in my BMW 840Ci?

Yes, you can run components in front and coaxials in rear. This is actually a smart approach for the BMW 840Ci since both locations accept 5.25-inch speakers. Install components in the front door panels for detailed highs and mids, then keep simpler coaxials in the rear. The impedance should match - most aftermarket speakers are 4-ohm which works fine with your factory system. Just make sure your front components can handle at least 20-30 watts RMS. The rear coaxials don't need as much power since they're mainly for fill.

What power handling should I look for in BMW 840Ci replacement speakers?

Target 25-50 watts RMS for the 5.25-inch speakers in your BMW 840Ci. The factory system probably pushes around 20-25 watts per channel, so anything in that range will work without an amplifier upgrade. Peak power ratings don't matter much - focus on RMS. If you're adding an aftermarket head unit later, speakers that handle up to 75 watts RMS give you room to grow. Component speakers typically need slightly more power than coaxials because you're driving the woofer and tweeter separately. The BMW 840Ci's door panels have decent mounting depth, so most standard 5.25-inch speakers should fit without modification.

Why does my BMW 840Ci have midrange listed as an option for front speakers?

The midrange designation means some BMW 840Ci models came with a dedicated midrange driver in the front doors, probably part of a factory premium audio system. This would be separate from any tweeter or woofer. If your car has this setup, you might see a smaller speaker (maybe 3-4 inches) handling just the middle frequencies around 500Hz to 4kHz. When replacing these, you need to maintain that frequency split or convert to a full-range coaxial system. Check your current setup carefully - if there's a separate tweeter somewhere in the door or dash, you're dealing with a component system that needs matched replacement parts.