Bass-reflex for Fostex FE-103 sigma

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Hi all,

I want to build a pair of minimonitors with fostex's FE 103 or FE 103 sigmas. I was thinking in using the plans for the FE 103 available at fostex's homepage, but I've been told that the Sigma version sounds much better.
How the Sigmas would work in a little bass-reflex enclosure? (I know they are widely used in folded horns, but have no information about mini-sized vented box) Does anybody know if there are published plans for such a configuration?

Thank you,

Thank you very much for your replies.

I've been checking both sites, and I think I will end with the Sigmas, but in a smaller enclosure than "Le petit", which seems a very simple and nice project (but not so "petit", after all, at least not for my current needs).

If anyone is interested in how it all ends, just let me know.

;) Thanks Vladimir! My french is a bit rusty but I'll manage my way through it. My first experiment with a 103S (my first building project anyway) was a TQWP called 'solo' as you can see on the picture attached.

The white monsters (a bit bigger design) are a recent aquisition of mine, it's an early design from Bert Doppenberg ( from the Netherlands. The guy used to be a member of the audio association that Bert started and lived close by.

The guy who sold them (my bid was 57,5 euro!!!, the units alone are worth that) was running into some 'female impedance', the picture attached leaves no doubt! There was only one speaker per enclosure but I am going to experiment with two of them (in series, makes it 16 ohm). At this moment I have to wait since my amp is being redesigned for 300B tubes and a pair of black gates are being added by my (very technical) friend Jasper.

Even with one small 103S you will be amazed what sound it produces, okay, no deepest sub bass but my sub has been idle for some time now! It is so musical and warm yet clear, nothing you'd expect from such a tiny speaker. Next thing I need is a bigger house but so what!

I havn't got the exact plans but I am thinking of inquiring with Bert Doppenberg to find a way to get the speaker cable on the back of the enclosures. If you are interested, let me know at ''.



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