R35 GTR Twin Utopia System (2009-14)


This item is for a turn-key system designed for 2009-2014 R35 GT-Rs to upgrade from the factory Bose subwoofers. This is a direct plug and play replacement with no wires needing to be cut or holes drilled. This particular system is equipped with Focal Utopia Be21 WX subwoofers that produce ultra accurate, deep, and a very punchy sound. The Focal Be21 represents the pinnacle of quality from Focal who has been a long standing icon in the audio industry. Manufacturing their own drivers, Focal retains the very best of technology for their own equipment. This flagship subwoofer is among the top 8″ subwoofers ever made. The Focal Be21 WX produces ultra accurate and deep bass. Although this system does perform very well, it is important to note that this is a sound quality subwoofer. This system is a special order request item.

Housing the Be21 subwoofers is the specially produced, Utopia slope box. Although the Utopia box is similar looking to the Gen5 twin 8 enclosure, it is in fact very different and takes about double the time to produce. The enclosure is built from a 5/8″ MDF skeleton for structural rigidity and sound quality. An internal skeleton design allows for greater internal volume to be achieved while maintaining strength and reducing weight. In this design, the subwoofers are not recessed into the box, but instead raised rings are added to build and contour the enclosure around the subwoofers. Each section of the skeleton is rounded off and there are no sharp corners anywhere on the inside of the box. The outside of the box is meticulously hand sanded to result in a beautiful shape. The Utopia box is 5lb lighter than the Gen5 twin box, is stronger, and has more internal volume with less air turbulence. The enclosure is finished with gold hardware, gold terminals, and a 1/4″ layer of high density foam with upholstery that is nearly identical to the factory GTR interior. A rear centre console cover and rear deck cover is included to carry the OEM stitching from the front arm rest, through the rear console, and onto the subwoofer enclosure.

Everything you need for the install is included, with the exception of tools. The install time takes approximately two hours depending on your install ability. This is a plug and play style install. All bolts match up to factory bolt locations, no wire cutting is required, no holes need to be drilled, and the front seats do not need to be removed. The amplifier will be sent pre-tuned to sound great as soon as it is installed. Tools required for the install are a flat screwdriver, 10mm socket driver, 14mm socket driver, 4mm Allen key. This kit includes:

  • Xtreme Audio twin 8″ sealed curved subwoofer enclosure
  • 2 Focal Utopia Be21 WX subwoofers
  • JL Audio MX500 amplifier
  • LOC90 line converter with gain control
  • Amplifier rack
  • Pre-built plug and play wiring harness
  • Enclosure mounting brackets and hardware
  • Rear console cover
  • Rear deck cover


Out of stock



Technical Specifications

  • 500 RMS watts (continuous power handling).
  • 10mm excursion
  • 86.5db sensitivity
  • 208.6cm^2 Surface area (per sub)
  • 2 ohm load
  • Gold plated speaker terminals
  • 10 gauge pure copper speaker wire

Please see the comparative sound chart below. Note that the phrasing is very generalized and the performance and sound quality are excellent for all options. There are however slight differences between the final sound of each system as a result of the different technologies that each subwoofer manufacture uses such as their cones, venting, magnets, etc