05 May 2008

Fostex FX120 ML-TQWT Speaker Project

Martin from Germany has put together a great looking pair of tower loudspeakers. His speaker project uses the Fostex FX120 fullrange driver. I have used this driver myself and it is my favorite Fostex driver.

Fostex FX120 Fullrange Driver Speaker
The speaker enclosure is a Mass Loaded - Tapered Quarter Wavelength Tube (ML-TQWT). As you can see, Martin has done a great job with the finish on the DIY speaker cabinet. He came up with the design on his own using the MathCAD worksheets available from Martin J. King at quarter-wave.com. His speaker project includes a design for a baffle step correction circuit which he found necessary to balance the sound.

DIY Fostex FX120 Transmission Line Speaker Project

Martin reports that the sound is relaxed with a detailed midrange and good highs. He also indicates that the ML-TQWT enclosure gets good low end extension from the small Fostex driver. Having recently used the FX120, I can confirm that this is one sweet sounding driver.

For additional information, pictures and the speaker cabinet design, see Martin's Fostex FX120 DIY ML-TQWT Speaker Project.

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  1. An extremely good looking and very well made pair of speakers around some very respected drivers. If the builder lived in the same state I would be commissioning him to build me a pair. 10 out of 10!

  2. Great looking enclosure. I have used the Fostex FX120 transducer as well as many other full-range units and it is the best one of the lot.