Speaker Break-In, Case of Difficulty

used and at or above 3.5kHz if you are using an 18 or 24dB per octave crossover. In this configuration, the crossovers supplied with the 408 and 508GTi are not used. For tweeter protection, a 1.5A fast acting fuse should be installed in series with the tweeter. The maximum recommended RMS amplifier power routed directly to the woofer/midrange is 150 watts for the 408GTi and 200 watts for the 508GTi. The maximum recommended RMS amplifier power routed directly to the tweeter is 125 watts.

Speaker Break-In

The 408 and 508GTi Woofer/ Midranges use many high strength materials which require a break-in period before they will achieve top performance. The drivers need to be broken in at a medium volume level for about 1 hour before maximum performance is achieved.

A Note on Power Handling

As a result of their high efficiency, all

JBL loudspeakers will produce reasonable volume levels in the automotive environment using very little amplifier power. However, the use of a low-powered amplifier to attain very high volume levels could lead to overdriving the amplifier. This will generate high distortion levels which can easily damage loudspeakers, even if the rated power of the amplifier is below the rated maximum power handling of the loudspeaker!

As a general rule, do not turn up the volume control past the point where you hear distortion in the form of either signal distortion from an overdriven amplifier or mechanical noise from an overstressed speaker. For the best performance and system reliability, you should select an amplifier with an output rating greater than the maximum power likely to be used to generate the desired volume levels. If you want your system “Loud + Clear,” we suggest that you step up to a JBL power amplifier which has an RMS power rating equal to, but not exceeding, the Maximum Recommended Amplifier Power listed in the specifications of your specific JBL

speaker. This margin of reserve power will ensure that the amplifier will not attempt to deliver more power than its design allows. Your dealer will be happy to point out which high power JBL amplifiers are optimum for your application and listening habits.

Following these guidelines will provide virtually distortion free sound reproduction and long loudspeaker life.

In Case of Difficulty

The most common difficulties are noise, distortion, and intermittent connections.

System noise is usually not the fault of the 408 and 508GTi. Hiss or “alternator whine” is most often the result of faulty grounding of the system electronics or improper setting of amplifier level controls. An exception to this is if the passive crossover networks are mounted near a source of radiated noise, the network may pick up this noise with sufficient power to drive the 408 and 508GTi. For this reason, be careful not to mount any passive

508GTI specifications

The JBL 508GTI is a remarkable addition to the world of professional audio monitors, designed to satisfy discerning listeners as well as studio professionals. With its striking design and cutting-edge technology, the 508GTI offers an impressive listening experience tailored for various audio applications, from music production to film scoring.

At the heart of the 508GTI lies a 5-inch low-frequency woofer made of a proprietary polypropylene composite, ensuring excellent bass response and clarity. This cone design minimizes distortion, allowing for clean reproduction of bass frequencies down to 45 Hz. Complementing the woofer is a 1-inch titanium dome tweeter that delivers smooth and precise high frequencies up to 40 kHz. This wide frequency response ensures that the 508GTI reproduces audio accurately, making it easier for sound engineers to mix music that translates well across different playback systems.

One of the standout features of the JBL 508GTI is its innovative Image Control Waveguide technology. This sophisticated design optimizes the speaker's dispersion pattern, allowing for a larger sweet spot while maintaining excellent stereo imaging. As a result, listeners can enjoy an immersive sound experience even when they are not seated directly in front of the monitors.

The 508GTI also incorporates advanced bi-amplification, utilizing separate amplifiers for the woofer and tweeter. With a total power output of 82 watts, this design ensures that each driver operates at its peak performance without compromise. Additionally, the built-in DSP processing allows users to tailor the speaker’s performance to their specific acoustic environment, making it highly versatile for any studio setting.

Connectivity options on the JBL 508GTI include XLR and TRS balanced inputs, providing flexibility for various professional audio sources. The speaker is also equipped with rear controls for adjusting high and low-frequency response, enabling users to optimize their listening experience based on the room's acoustics.

In summary, the JBL 508GTI combines premium materials, innovative technologies, and versatile features, making it an exceptional choice for audio professionals seeking accuracy and reliability. Its blend of performance, design, and functionality ensures that it stands out in the competitive field of nearfield monitors, delivering a listening experience that is both enjoyable and precise.