Fostex FX120 Fullrange Speaker Driver
Fostex FX120 Fullrange Speaker Driver
The Fostex FX120 is a 125 mm (5") cone type full-range speaker. Consistent with most Fostex drivers, the FX120 is well built and it sounds excellent. Unlike the lower cost and more popular Fostex fullrange drivers which use a stamped frame, the FX120 is constructed on a cast frame. The cone is constructed out of KENAF paper which is a fiber composite and is suspended with a rubber surround. The dust cap is metallic. The magnet is large, weighing 330 grams. Of the Fostex Fullrange speakers, the FX120 has the greatest Xmax at 2 mm. The Xmax of the similar sized Fostex FE103E, FE126E and FE127E is only about 0.35 to 0.4 mm, while the much larger 6.5" FE166E/FE167E and the 8" FE206E/FE207E still fall short with only 0.6 mm and 1.5 mm respectively. The FX120 can be used in a wide variety of enclosures, but is best suited to bass reflex, Transmission Line and Quarter Wavelength enclosures.
Photograph 1: Fostex FX120 Fullrange Speaker
The datasheet below includes the Thiele / Small (T/S) parameters for the driver. For those who are looking to design a Zobel / Impedance Equalization Circuit for the FX120, I have measured the voice coil inductance (Le) of my drivers as it is not included in the datasheet. The inductance I measured on two drivers with a Sencore LC75 meter is 0.11 and 0.12 mH.
Datasheet and Enclosure Plans - Fostex FX120
- Fostex FX120 Driver Datasheet - (PDF - 109kB)
- Fostex FX120 Recommended Bass Reflex Enclosure Drawings / Plans
Projects Links - Fostex FX120
- Fostex FX120 Bookshelf Bass Reflex Speakers
- Fostex FX120 TQWT - (External Link)
- Fostex FX120 and Eminence Alpha 10 - (External Link)
- Fostex FX120 ML-TQWT (transmission line) Speakers