JBL GT5-12 Subwoofer with 1.0 CuFt Sealed Enclosure

275W 12" GT Series Single 4 ohm Subwoofer and Sealed Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.0 cu ft airspace)

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Big Bass

For anyone who likes to crank it up in the car, the new JBL 12" high-output GT5-12 subwoofer is the real deal. The JBL GT5-12 subwoofer features a single 4-ohm voice coil and a vented motor structure, and offers 1100 watts of peak power handling. The GT5-12 also features JBL’s newest design, combining classic elements with modern ones.

All-New Design

The GT5-12 follows the design of the more-expensive JBL subwoofers, combining classic elements with modern ones.

Significant Power Handling Capabilities

The GT5-12 handles 275W/1100W (RMS/Peak) power and offers nearly 20 percent higher Xmax than many competitors.

Increased Reliability

With its fully vented motor structure and rubber-coated tinsel leads, the GT5-12 is able to withstand even the most intense bass assault.

Dual-Stacked, Oversized Magnets

Unlike competing entry-level subwoofers, the GT5-12 is based on a solid motor structure featuring two large magnets covered by the classic JBL rubber ring.

The Sound of quality

Sonic Electronix, one of the leaders in car audio, recently visited Harman, the premium global audio and infotainment group, at their research and development locations in Northridge, California and Detroit, Michigan. The purpose of these visits was to utilize and combine the powerful brand of Harman and the industry leading knowledge behind Sonic Electronix to begin working together on developing future car audio projects.

JBL GT5-12

275W 12" GT Series Single 4 ohm Subwoofer
Quantity: 1

General Features:

  • 12" Single 4 Ohm GT Series Subwoofer
  • Power Handling:
    • Peak: 1100 watts
    • RMS: 275 watts
  • Impedance: Single 4 ohm
  • Polypropylene cone woofer
  • Rubber surround
  • Rubber coated tinsel leads
  • Vented motor structure
  • Single 4 ohm voice coil
  • Dual-stacked, oversized magnets
  • Frequency response: 27-450 Hz
  • Sensitivity: 90 dB
  • Authorized Internet Dealer
  • 1-year Manufacturer's warranty

Single 12" Sealed MDF Subwoofer Enclosure (Belva MDFS12)

12-inch Sealed Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.0 cu ft airspace 12SQTC)
Quantity: 1

General Features:

  • Single Sealed 12" Enclosure
  • Internal box volume: 1.0 cubic ft
  • High Quality 3/4" MDF Construction
  • Durable black carpeting
  • Pre-lined with Poly-Fil
  • Seams are fully caulked for better efficiency
  • Gold post terminals for clean and easy wiring access
  • Box Dimensions: 14-1/4"L x 14-1/4"D x 14-1/4"H
  • 30 Day return policy


Second Depth
The second depth is used only when the box is slanted or angled. This value is the top measurement and it is measured in inches.
The front-to-rear depth of the item, in inches. If the item is angled or slanted, this value is the bottom measurement.
The height of the item, measured from top to bottom, in inches.
The width of the item from left to right (side-to-side) measured in inches.
Color of handle.

Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider

Summary of Customer Ratings & Reviews

Rating Distribution

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Average Attribution Rating

Browse 1 question and 1 answer
Hide answersShow all answers | Sort by
The sub ships assembled to enclosure?
sergioge on Jul 5, 2016
Best Answer: Hi Sergio,

It does NOT.
Reply · Report · Rick MStaff on Jul 5, 2016
· Add Answer · I Have This Question Too (0)

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Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: JBL GT5-12 Subwoofer with 1.0 CuFt Sealed Enclosure

Item Added to Cart

JBL GT5-12 Subwoofer with 1.0 CuFt Sealed Enclosure

275W 12" GT Series Single 4 ohm Subwoofer and Sealed Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.0 cu ft airspace)


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