Problem with BIB-165K sim


2003-08-12 8:43 am
I'm working on BIB Fostex FF165K sim, but I have some problems, or missuderstanding.
When I put T/S data into BIB_166_GM_v2 sheat , I get L=168,31 in. and Sm=93.50 (more that on Zilla site - Sm=88.125
If I shorten L and change Fr to 50Hz, then Sm become bigger (Sm=116.87
What I'm doing wrong?
How to calculate shorter pipe?
I think that Sm must be the same - not bigger if pipe L shorten?


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It takes 'x' amount of net volume (Vb) per Hz of gain BW and when you shorten it you're reducing Vb, so the wall angle and base area must increase to offset the loss in pipe loading. IOW no matter what Fp you choose, the net Vb stays the same whether tall and narrow or short and wide, though there's a point at both extremes where the simple math returns an unacceptably performing alignment.


I was too and frankly knew that I'd screwed up, but due to a variety of factors beyond my control at the time I couldn't find it, so posted it anyway figuring Scott would review/correct as required since he gets up in an earlier time zone, but he didn't.

Anyway, I found my multiple inputting errors:



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Sorry guys & particularly Greg. I thought there was something wrong, but I didn't have time to look into it this morning, as I needed to get over to Salford to meet some Pakistani naval commanders. Glad it's sorted out though. The 165 really does have a bit of magic in this load, despite the limited Xmax. Not one for belting out Iron Maiden, but if you like acoustic music in particular, you're laughing.