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    GRS B100C-4 ASD Series 4" Glass Fiber Cone Coaxial Speaker Pair Upgrade Kit for Select BMW Models

    € 123,93€ 149,95 Out of stock: delivery time is 1 week
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    Product description

    The GRS B100C-4 4" BMW replacement full-range driver pair is the perfect solution for dealerships, installers, and repair shops. The unique swappable mounting flange allows this speaker to replace virtually all 4" drivers used in late model BMW vehicles taking all the guesswork out of which driver to order or stock for factory replacements and upgrades.



    • Exclusive adaptable frame design fits practically all 4" drivers used in late model BMW vehicles
    • Woven fiberglass cone, rubber surround, and poly frame is weather and UV resistant
    • Powerful neodymium motor produces high efficiency with low distortion
    • Includes all gaskets and wiring harnesses needed for a drop in replacement
    • A true plug-n-play system and completely reversible


    Product details

    GRS B100C-4 ASD Series 4" Glass Fiber Cone Coaxial Speaker Pair Upgrade Kit for Select BMW Models


    Take all the guesswork out of which speaker to use when replacing BMW 4" factory coaxial speakers with the GRS B100C-4 speaker pair. Factory 4" speakers in most BMW vehicles come is a variety of mounting flange configurations, making selecting the proper replacement a difficult task, but thanks to the exclusive swappable mounting flange this speaker can replace nearly all 4" drivers used in late model BMW vehicles (please check the GRS B100 BMW Compatibility Chart for your vehicle). Just select the proper mounting flange and gaskets (all included), attach the flange to the driver with four screws, and then drop the speaker into the factory mount for a perfect fit. In addition, with the included wiring harness the B100C-4 are true plug-n-play, no need to cut the factory wiring harness or strip wires. Thanks to the GRS B100C-4 there is no reason to keep three different drivers in stock or wait for months to get your customers the proper replacements for their vehicle making these the ultimate replacement/upgrade speakers for late model BMW vehicles.


    The GRS B100C-4 is more than just a unique mounting flange; the highest standards have been applied to every aspect of these speakers. The woofer uses a woven glass fiber cone, poly dust cap, and rubber surround designed to keep resonances under control and provide natural response while resisting the extreme temperatures, moisture, and direct UV exposure that car speakers are exposed to. Venting behind the spider and through the motor assembly circulates air around the voice coil allowing high power handling and keeping compression low. The motor consists of a powerful neodymium magnet that is surrounded by a generous piece of polished steel, which provides excellent heat dissipation required for long listening sessions during road trips. For high frequencies, the B100C-4 includes a robust, coaxially mounted 7/8" soft dome tweeter. With a natural silk diaphragm and powerful neodymium motor, this tweeter will produce detailed high frequency response with minimal distortion.



    Note: Sold in pairs.


    Article number
    Woofer Series
    Replacement woofer
    Nominal Diameter
    Power Handling (RMS)
    40 Watts
    Power Handling (max)
    80 Watts
    Impedance (Z)
    4 ohms
    89.77 dB 2.83V/1m
    Frequency Response
    70 to 20,000 Hz
    Voice Coil Diameter
    DC Resistance (Re)
    3.2 ohms
    Voice Coil Inductance (Le)
    0.25 mH
    Resonant Frequency (Fs)
    118.4 Hz
    Mechanical Q (Qms)
    Electromagnetic Q (Qes)
    Total Q (Qts)
    Diaphragm Mass Inc. Airload (Mms)
    Mechanical Compliance of Suspension (Cms)
    0.36 mm/N
    Surface Area of Cone (Sd)
    52.81 cm²
    BL Product (BL)
    3.53 Tm
    Compliance Equivalent Volume (Vas)
    0.049 ft.³
    Cone / Diaphragm Material
    Surround Material
    Voice Coil Wire Material
    Voice Coil Former
    Kapton® / Polyimide
    Basket / Frame Material
    Magnet Material
    Overall Outside Diameter
    Overall Depth
    Baffle Cutout Diameter
    # Mounting Holes
    Sealed Volume
    0.078 ft.³
    Sealed F3
    129 Hz
    Vented Volume
    0.21 ft.³
    Vented F3
    70 Hz


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    B100C-4 ASD Series 4" Glass Fiber Cone Coaxial Speaker Pair Upgrade Kit for Select BMW Models
    € 123,93
    € 149,95
    B100C-4 ASD Series 4" Glass Fiber Cone Coaxial Speaker Pair Upgrade Kit for Select BMW Models
    0 In stock: delivery time is 1 week
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