F30/F80 Add-A-Sub Level Two


Add-A-Sub Upgrade Level Two for BMW F30 3-Series Sedan, F80 M3 Sedan with 688

The signal is interfaced with using a plug-and-play harness (no cutting) which we prep for the specific system. The signal is routed through a high-voltage-capable attenuating buffer amplifier (the H/K amplifier can reach peaks of 28 volts to the stock 8-ohm woofers, so it’s important to reduce that signal to a level which the new amplifier can handle).

Then we send the sub-bass notes to the driver in the Musicar OE-Look Subwoofer Enclosure.

  • Corner-loading gets you more output than a comparable “on-the-floor box”.
  • The “OE-Look” upholstery has been hand-dyed to match your BMW trunk
  • As a Musicar design element, the woofer is recessed 19mm from the outer edge
  • All mounting hardware and wiring is included
Level Two
  • 500 watts RMS for the subwoofer
  • amplifier rack (installs out of sight under floor)
  • active crossover filter
  • plug-in integration harness prewired to high-voltage attenuator
  • loaded enclosure with 10-inch high-output subwoofer



Application Notes

This package does not fit the F32 coupe, F34 3-Series GT, or the F31 touring. It is for F3o and F80 sedans 688 H/K audio systems (if you have 676 HiFi, contact us, thanks!)

The Level Two package sends 500 watts of continuous RMS power to a high-output 10-inch subwoofer with integrated grille.

The installation is plug-and-play to the HK amplifier, and our equipment rack bolts into existing trunk holes. The turn-on wire requires a single connection, without cutting. There are two holes to drill out of sight for wire passage – they are very hard to find afterwards. For these reasons, we recommend professional installation.

The enclosure mounts with a single bolt through the inside of the enclosure, to a receiver we provide which bolts to an existing bracket.

Our harness includes a center-delete loop, which allows you to easily test our recommended “surround off, center delete” setup for the H/K audio package.



Additional information

Level One

300 watts for the subwoofer and around 50 watts per underseat woofer

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