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Focal Inside ISUB BMW4 Integration Focal Inside Series 8" 4-ohm component subwoofer for select BMW models

Item # 091ISUBMW4

If the bass from your BMW's sub system isn't cutting it, add some punch "a la Francaise" with this Focal sub...

Find what Fits your vehicle

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If the bass from your BMW's sub system isn't cutting it, add some punch "a la Francaise" with this Focal sub...

Item # 091ISUBMW4

Every order includes

  • Free lifetime tech support
  • 60-day price-drop protection
  • 60-day returns
In stock

Deeply discounted installation gear

$589.99 each

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Expert help 400+ hours training Virginia-based

About the Focal Inside ISUB BMW4

Ken Nail

Product highlights:

  • single 8" 4-ohm component subwoofer
  • designed for specific BMW models
  • Polyglass woofer cone
  • butyl rubber surround
  • neodymium magnet
  • power handling: 90 watts RMS (180 watts peak)
  • frequency response: 35-200 Hz
  • sensitivity: 83 dB
  • grille not included
  • warranty: 1 year
  • MFR # ISUBBMW4
  • Item # 091ISUBMW4

What's in the box:

Focal Inside ISUB BMW4 owner's manual

If you need assistance accessing this owner's manual, please give us a call.
  • 1 Subwoofer
  • 1 Foam gasket
  • Four 1" Screws
  • User manual (English/ French/ German/ Italian/ Spanish/ Portugese/ Dutch/ Polish/ Russian/ Chinese/ Korean/ Japanese/ Arabic)
  • Focal window sticker
  • Adhesive backed Focal Inside badge

More details on the Focal Inside ISUB BMW4

Pat M.

Features & specs

General
Speaker Size Vehicle-specific
Driver Design 1-way
Woofer Design Cone
Woofer Material Polyglass/Paper
Woofer Surround Butyl Rubber
Midrange Design ---
Midrange Material ---
Tweeter Design ---
Tweeter Material ---
Super Tweeter Design ---
Super Tweeter Material ---
Impedance (Ohms) 4
Weather-resistant No
Grilles Included No
Parts Warranty 1 Year
Labor Warranty 1 Year
Specifications
Sensitivity (1W at 1 meter) N/A
Sensitivity at 2.83 volts 83
Frequency Response 35 - 0.2k Hz
Maximum RMS Wattage 90
Peak Power Handling (Watts) 180
Top-mount Depth (Inches) 1 7/16
Bottom-mount Depth (Inches) N/A
Cutout Diameter or Length (inches) 7 7/16
Mounting Height (Inches) 0.91
Frame Width 8.5
Frame Length 8.5

Product Research

Features

Mounting: The ISUB BMW 4 is a direct replacement for the factory under-seat subwoofers in select BMW models. In most cases, the new sub has the same screw hole pattern as the factory sub and is a perfect fit, but there are a few instances where the factory sub was glued in place and new screw holes need to be drilled in the plastic factory enclosure. The factory grille is re-installed over the new subwoofer. This sub is packaged individually, so you will need to purchase two. Please enter your vehicle information to confirm fit.

Wiring: The BMW factory wiring harness plugs directly into the subwoofer frame.

Polyglass Cone: The subwoofer cone has a cellulose pulp base and is coated with a uniform deposit of hollow glass microballs. The addition of the Polyglass layer significantly increases the cone's rigidity without adding much weight. This combination takes advantage of the accuracy and neutrality of the hard outer surface, but maintains the superior damping characteristics of the cellulose pulp. The subwoofer has a built-in cover, so the cone isn't visible during installation.

Magnets: The sub uses a neodymium magnet to minimize size without giving up magnetic field strength.

Reinstalling Seats: When researching a previous generation BMW replacement subwoofer, I found a warning about not reconnecting the battery until the seats have been reinstalled and the wiring reconnected. The warning stated that reconnecting power too soon, to test the new subs, can damage the seats and airbags. I found no such warning related to this ISUB BMW 4 sub, but to be safe I recommend heeding the warning in this case as well.

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Focal Inside ISUB for BMW
$589.99 each
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