Option Audio BM-165 6.5 Inch Subwoofer for BMW i4 150w RMS
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The Option Audio BM-165 is a 6.5 inch (16.5cm) plug & play dual voice coil subwoofer for the BMW i4, rated at 150W RMS with a shallow 3.5cm installation depth. It belongs to the Option Audio vehicle-specific upgrade range.
Key specifications
- Size: 16.5cm (6.5in)
- Vehicle: BMW i4 (replaces the original woofers in the 3-way system)
- Voice coil: dual, 4 ohm + 4 ohm
- Power handling: 150W RMS
- Installation depth: 3.5cm
- Magnet: neodymium
- Weight: approx. 500g per subwoofer
Subwoofer for BMW i4 | 16.5cm woofer | Plug & Play | Option Audio
The BM-165 is designed specifically to replace the original woofers in the BMW i4's 3-way system via plug & play, with no complex wiring required. It delivers clear, dynamic bass reproduction matched to the acoustic requirements of the i4. The dual voice coil improves efficiency, and the compact 3.5cm installation depth ensures a clean fit in the factory mounting locations.
At approximately 500g per unit, the BM-165 is well suited to door mounting — the low mass reduces momentum when the door is slammed. This weight saving is achieved through the use of a neodymium magnet, which saves around 2kg compared to an equivalent ferrite magnet design. If you're looking for a universal flat alternative, Option Audio also produce the AIR-F6 D2, a 6.5 inch dual voice coil flat subwoofer rated at 150W RMS.
Explore the full range in Option Audio Plug & Play.
Specification
| Diameter | 16.5 cm |
|---|---|
| Voice coil | Double |
| Impedance | 4 Ohm + 4 Ohm |
| Power handling | in watts (RMS) 150 |
| Installation depth | 3.5 cm |
| Magnet | Neodymium |
What's Included
- 1x OPTION Audio BM-165
Option Audio
About the Option Audio BM-165
From our tech experts at CEN
An Option Audio 6.5 inch subwoofer, handling 150w RMS.
Who it suits
Drivers adding low end to a system, and van and camper builds where space is the binding constraint.
Our tech experts advise
Enclosure volume and tuning decide most of what you hear. We build enclosures to suit both driver and vehicle at our Beeston workshop. Installation is priced per vehicle, so get in touch with your make, model and year and we will confirm what it needs. See car audio installation.
Explore the full Option Audio range at CEN, with fast UK dispatch and expert advice from our Nottingham team. Shop all Option Audio
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Have it Fitted By Our Team
Our team fits car audio, stereos, dash cams and vehicle security at our workshop in Beeston, Nottingham. Tell us your vehicle and we'll confirm the parts and a fitted price.
- 1
Tell us your vehicle
Make, model and year, and what you'd like fitted.
- 2
We confirm the parts
Fascia, wiring and interfaces checked for your car, with a fitted price.
- 3
Fitted at our workshop
Bring it to our Beeston workshop and we do the rest.
Unit 25 Technology Drive, Beeston, Nottingham NG9 1LA
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Frequently Asked Questions
Q: Do I need an amplifier for this subwoofer?
A: Yes, unless it is an active (powered) subwoofer with a built-in amplifier. Passive subwoofers need an external amplifier matched to the RMS power and impedance shown in the Specification tab.
Q: What does RMS power mean?
A: RMS is the continuous power a subwoofer can handle, and it is the number that matters when matching an amplifier. Peak or max figures describe short bursts only. Match your amplifier output to the RMS rating in the Specification tab.
Q: Which car is the Option Audio BM-165 for?
A: It is specially developed for the BMW i4, replacing the original woofers in the 3-way system and fitting the designated installation slots.
Q: How deep is the BM-165?
A: It has a compact installation depth of just 3.5cm.
Q: Why is a light woofer better in a door?
A: At approx. 500g, the BM-165 does not generate much momentum when the door is slammed. The low weight comes from its neodymium magnet.
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