- 2008-02-22 1:21 pm
Helmholtz is very straightforward and maybe you are missing some parameters.
Maybe this helps, post (your) results.
Résonateur de Helmholtz
WinISD or its pro version? The former hasn't been very accurate IME, though the latter is OK for cube or low aspect ratio rectangular cabs. For higher aspect ratios you'll need MJK's MathCad software or maybe AkAbak to find the proper vent length empirically.