Fostex FE207E bass reflex enclosure

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Hi all,

What is the correct lenght of the vent tube in this Fostex drawing? 18mm seems wrong.


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It's a Typo!

I actually built the darn thing with the 18mm port just to see if it sounded right. Nope, it didn't.

So I plunked down $25 for Bob Brine's FB-20 plan and it was definitely worth it. His plan is a considerable refinement, with a lot more detail, different volume, construction photos, etc. and includes the BSC diagram, a parts list (e.g., Parts Express port tube part number -- cutting PVC cleanly is not as easy as I thought.) etc. I am really psyched to short-cut a lot of trial and error.

Bob mentioned that they are probably just missing a zero, i.e. 180mm. But if they're missing a zero, and didn't notice, how optimal is this box? I'd consider going with Bob's plan if you want an additional level of refinement. Mine are almost done.


Joined 2003

Well, assuming they mean 180 mm, it's about right for a Fb = Fs alignment that when driven with a high output impedance amp should be nominally flat, so if SS driven either a higher Fb is required or a BSC filter to tonally flatten it with some loss of peak efficiency.

Plan for FE207e in 45 liter box?

Hi Godzilla,

(a) Are you referring to the recommended double BR?

(b) Is there anywhere you have posted your mods, or your thoughts on what to mod? E.g., are you just tuning the port differently or...

I am an extreme newb, sorry if these questions have obvious answers.
>>> (a) Are you referring to the recommended double BR?

No, just a simple 46L bass reflex box.

I like swapping drivers out to hear what they sound like. I have swapped a Radio Shack 1354 and Fostex 127e in a Straight Pipe, a Fostex 168S and 165k in a BIB. I wanted to try the 8 inch Fostex drivers to see how they sound so i am curious about the 207e in a br box. For the 207e, I can always build a BIB or the Double BR or a back horn of one design or another but to get an idea of how the driver sounds overall i was wondering if anyone had good luck with them in a simple BR. The older style 168S works best in a simple br box even after i built the BIB and a small back horn for them.

Has anyone build the 35L recommended box with good results for the 207e?

Both the 206e and 207e will go into a ~45l box. The result are quite good, although not as good as putting them in my big MLTL. The 207 needs a rather high tuned step filter and the 206e needs some serious attention to the rising FR. I haven't tackled a filter for the 206e yet. I am using the equalizer in Foobar2000 to tone it down.

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