Some time ago I found what could be called a 'non-official' 3rd Tempest alignment on this forum, vented and at 175L. I have been putting the figures into several programs, but I don't seem to be able to duplicate his results. - 175L net - Fb = 17,5 Hz - 10,2 cm port dia(4") - 43,2 cm port length - 150W - parallel connected - Stuff 100% (20gr. / liter) - F3 = 22 Hz anechoic Depending on fill (Qa) and leaking (Ql) I'm getting an F3 between 24,8 and 30 Hz, so not even close to 22Hz. After heaving read Tom Noussaine's article on stuffing I was under the impression that 100% stuffing should be avoided because it makes things worse. So why 100%? Going up to Fb = 19 gives me an F3 = 23,13 Hz which was the design I mentioned at the beginning of my thread about Sealed/Vented Tempest enclosures. Still I would like to be able to simulate Dan's design as close as possible. Has anyone calculated, simulated, built or heard this 175L design yet? Btw. Replacing the Tempest by a Shiva lowers Fb and F3 easily to 17-18Hz. Would this be better for my 70/30 music/movie usage, just giving up a little SPL? I already asked this question in another thread but on this particular question I didn't get any hands-on experience... Thanks for all reactions and remarks.