Choosing an Enclosure

Thank you for purchasing a new JBL GT Series subwoofer. Subwoofer installation often requires woodworking skills and some experience disassem- bling and reassembling automotive inte- riors. If you lack the tools or necessary skills, have your subwoofer installed by an authorized JBL dealer.

Warning: Playing loud music in an auto- mobile can permanently damage your hearing as well as hinder your ability to hear trafﬁc. We recommend listening at low levels while driving. JBL accepts no liability for hearing loss, bodily injury or property damage resulting from use or misuse of this product.

GT Series subwoofers are optimized to perform best in small sealed, vented and prefabricated bandpass enclosures. While inﬁnite-bafﬂe mounting of

GT Series subs is possible, power handling is greatly compromised because there’s no enclosed volume of air to prevent the speaker’s cone from moving past its limit. For this reason, we do not recommend inﬁnite-bafﬂe mounting for GT Series subwoofers.

You should choose the enclosure you will use based on the type of music you listen to, how much ampliﬁer power you will use for the subwoofer and how much space inside the vehicle you can devote to a subwoofer enclosure.

Because a sealed enclosure provides the most control over the woofer’s move- ment, a woofer mounted in a sealed enclosure can handle more power than a woofer mounted in another enclosure type. Sealed enclosures provide more accurate sonic reproduction than other enclosure types, so they are well suited to all types of music. Sealed-enclosure

construction is straightforward and there are many prefabricated sealed enclo- sures available. An optimum sealed enclosure is always smaller than other types of enclosures optimized for a par- ticular speaker, so they require the small- est amount of space inside the vehicle.

Vented enclosures provide better efﬁ- ciency in the 40Hz – 50Hz range, but this efﬁciency comes at the expense of sound in the lowest octave (below 40Hz), and at the expense of some control and power handling. If you are using a small ampliﬁer, a vented box will provide more bass output from less power. Vented enclosures are also well suited to a variety of music types. Because vented enclosures require the volume of the enclosure and the size of the port to have a speciﬁc relationship with the character- istics of the woofer, the enclosure must be built exactly to the speciﬁcations provided. While there are some prefabri- cated vented boxes available, matching a prefabricated box to a particular woofer is difﬁcult. If you wish to use a vented enclosure, we strongly recommend having your authorized JBL dealer build

it, or verify that your design is correct if you wish to build it yourself. An optimum vented enclosure is always larger than the optimum sealed box for the same woofer, and will require more space inside the vehicle.

Bandpass enclosures often provide the most output available from any ampliﬁer-and-subwoofer combination at the expense of sonic accuracy. If sheer SPL (sound-pressure level) is what you desire most, choose a bandpass enclosure. Bandpass-enclosure design is very tricky; using a computer and enclosure-design software is necessary. If you are an experienced installer or have some woodworking experience, you may wish to build the enclosure described in the Speciﬁcations chart in this manual. Fortunately, there are many prefabricated bandpass boxes available, and they are all optimized to extract the most output possible from any woofer. Bandpass enclosures can be quite large and may require a lot of space inside your vehicle.

GT1081, GT1041, GT1041D, GT1281, GT1241D specifications

JBL, a name synonymous with high-quality audio technology, offers a diverse range of subwoofers that cater to the needs of both casual listeners and audiophiles. Among their esteemed lineup are the JBL GT1241, GT1241D, GT1281, GT1041D, and GT1041 subwoofers, each designed to deliver powerful bass and unparalleled sound quality.

The JBL GT1241 and GT1241D are 12-inch subwoofers that provide impressive performance for those seeking deep, resonant bass in their audio systems. The GT1241 features a single voice coil design, while the GT1241D offers a dual voice coil configuration, allowing for flexible wiring options to match various amplifier setups. Both models utilize JBL’s advanced polypropylene cone technology, which ensures durability and reduced distortion, enabling them to handle high power levels without compromising sound clarity.

Similarly, the JBL GT1281 stands out with its 12-inch size and enhanced features that make it ideal for users looking for robust low-end performance. It offers a high power handling of 300 watts RMS, allowing it to produce deep bass notes that fill any space. The cone is crafted for optimal rigidity and minimal flex, which contributes to accurate bass reproduction even at higher volumes.

For those who prefer a compact design without sacrificing performance, the JBL GT1041 and GT1041D are 10-inch subwoofers that excel in tight spaces. The GT1041 features a single voice coil, while the GT1041D has a dual voice coil option. Both models are engineered with JBL's innovative designs that emphasize thermal management, ensuring that even during prolonged use, the subwoofers maintain their performance integrity.

A key highlight of all these models is JBL's patented rubber surround technology, which allows for greater excursion and better sound quality. This technology helps in achieving a deeper bass response while ensuring longevity and reliability. Additionally, their built-in venting systems provide effective heat dissipation, which enhances overall performance and durability.

Overall, the JBL GT series subwoofers, including the GT1241, GT1241D, GT1281, GT1041D, and GT1041, represent a blend of quality materials and innovative technology. They cater to various user needs, from high-powered setups to space-efficient options, while delivering the signature JBL sound that enthusiasts have come to love. Whether in a car audio system or a home theater setup, these subwoofers provide the deep, impactful bass that enhances any listening experience.