JBL GTO938

Refers to the size of the speakers.

Every vehicle has standard application sizes. Please contact us for your vehicle's specific speaker sizes if you do not know them.

The number of individual drivers in a car speaker. Speakers with 2 drivers are known as 2-way, 3 drivers = 3-way and so forth. Component systems are often referred to as "separates" because the tweeter is not attached to the midwoofer (main speaker driver) and mounts separately in a location such as a door post. Component systems typically come with an external crossover so you can easily adjust the high and low frequencies sent to both the midwoofer (main driver) and the tweeter. Center channel speakers are great for those looking to capture true surround sound in their car.

Designs such as cone, dome, semi-dome, balanced dome, and whizzer are most popular. Read below for a description of each and other designs.

Materials such as polypropylene, silk, cloth, and paper are the most common, where as many more recent tweeters are now manufactured with composites such as aluminum, titanium, Mylar, and other materials.

The woofer cone material is essential for efficient operation. Poly cones produce exceptional sound and are sturdy against various changes in temperature. Paper cones are very efficient, and when treated for moisture resistance, will perform at a high level. Poly refers to polypropylene: thermoplastic plastics or fibers that are polymers of propylene. IMPP refers to injection molded polypropylene, a commonly used process and material in speaker manufacture.

The flexible ring around the edge of the woofer cone. Surrounds are usually made of cloth, foam or rubber. Rubber and composites tend to last longer and hold up better in harsh environments.

Peak power handling refers to the amount of power a speaker can handle during a brief musical burst. The RMS power range figure is a much more reliable rating for determining the speaker's power requirements. The Peak power handling specification is typically rated per speaker unless otherwise noted.

The RMS power is the amount of power the speaker requires to operate safely and properly. RMS Power Handling refers to the amount of power a speaker can handle on a continuous basis. We recommend powering your speaker or subwoofer 75% - 90% of its recommended RMS rating. The RMS power handling specification is typically rated per speaker unless otherwise noted.

An efficiency or sensitivity rating tells you how effectively a speaker converts power into sound. The higher the number, the more efficient the speaker and the louder it will play with the same input power. An efficient speaker helps you maximize your available power. Most sensitivity ratings measure the speaker's output with 1 watt of input, 1 meter from the speaker. Some speakers' sensitivity is measured with 2.83 volts of input, instead of 1 watt.

Efficiency (1W/1m) is not an accurate indicator of a subwoofer's output capability and should not be used as a comparison to other subwoofers to determine which one is "louder".

The range of frequencies the speaker will reproduce (lowest frequency to the highest). Bigger is better, meaning the wider the range, the better. The optimal range is 20 - 20,000 Hz (which is the range of human hearing).

The load value (in ohms) that the speakers present to the amplifier per voice coil - the amount of resistance to the current flow. This is a key specification as subs wired in parallel or low impedances can create problems with your amplifier and potentially void all warranties. We encourage you to ask our support department prior to purchase if you do not understand which impedance level will suit you/your amp best.

The depth when installed on top of the mounting surface. Measured from the bottom of speaker(magnet) to the bottom of mounting holes on rim of speaker.(Most common application)

The depth when installed from bottom of the mounting surface. Measured from the bottom of speaker(magnet) to the top of the mounting holes on rim of speaker.

Refers to the hole dimensions (in inches or millimeters) needed to mount the speaker.