Several different types of compression drivers are available, each one designed for a specific speaker set-up. The different uses they are designed for include public speaking, outdoor concerts and nightclubs. Because of their different uses, their construction also varies, resulting in different weights and materials being used. The lightest compression drivers are between 9.5 lbs. and 10.5 lbs. in weight. The heaviest drivers range from 22.5 lbs. to 30.5 lbs.
The JBL compression drivers range between 70 watts, 100 watts, 120 watts and 200 watts. These are the power ratings when they are used in a continuous power mode. The JBL compression drivers are marked with a "H" or "J", or in some cases, with both. These letters represent the impedance levels of the compression driver. Anything with 8 ohm impedance is represented with "H" and anything with 16 ohm impedance is represented with "J." All of the drivers that have an output of less than 200 watts are marked with both letters as they can operate at both 8 and 16 ohm impedance. Models such as the "2490H MF" have an impedance of 8 ohms as represented in the lettering of the model number. This driver has an output of 200 watts at continuous power.
All of the JBL compression drivers are constructed of several high-quality materials. The diaphragm in all of the different compression driver models is made from pure titanium. The voice coil is edge wound and made of aluminum. The voice coil in all of the drivers measures four inches in length. In all of the drivers there is a copper-plated pole mount. This is used to reduce inductance which has an adverse effect on the output. By implementing the copper-plated pole, the high-frequency output is increased.