Stop the rise

[1200 bandit 2]

Hello family, I'm working on a design for my new SPL ( only ) enclosure. My last few enclosures had lots of impedance rise and I would like this one not to. Are there so thing I can do to help keep the rise down? A little more info for you. Box 1.8cuft, port 6" Precision Port tuned to 44hz., 3/4 birch x2 baffle. The sub is a Kicker solo X 10 D1 any help would be great. Wise guys need not reply I have no time to play.

[KU40 173]

Impedance shift will always be there. You can't get rid of it. You can limit it, however. To get an idea, download winISD alpha, input your sub's parameters, and look at the impedance graph. It won't be exactly accurate, but it will give you an idea of what's going on and what shifts to box parameters will adjust the shift and its amplitude. Or if you have the appropriate equipment, you can take measurements with test tones and make your own graph. But I'll tell you that sometimes it's not so much eliminating the amount of impedance rise as just moving where the rise occurs. Since you're just doing a one-note wonder box, you're only going to worry about impedance at that frequency. So maybe playing with the box parameters just so that the impedance curve moves over a few hertz so that you're in a trough instead of a peak in the impedance chart, that may work.

Generally impedance is lowest at tuning and sweeps up from there both above and below tuning. Tuning higher lowers the amplitude of the curve above tuning frequency, and increasing box size lowers that peak as well. But, if you increase box size you take away mechanical power handling, so that's a bit of a balancing act.

[1200 bandit 2]

Thank you KU40, time to do some homework.

[imhungnurnot 9]

Good information. So i'm in the same boat. If i find my resonant frequency of my vehicle, what should I tune to? I read a few times on here to tune the enclosure from a few hz to ten hz below resonant freq. What seems correct; a few below or ten below? After that, adjust box parameters in winISD to get my resonant freq in a trough in the graph.

[Randal Johnson 544]

[imhungnurnot 9]

Helpful! lol

[Duran 387]

Want to stop impedance rice? I'll tell you how. Clap three times, do a backflip and say "Stopeth the riseth!" Then ta-da! The rise will be gone.

[imhungnurnot 9]

Want to stop impedance rice? I'll tell you how. Clap three times, do a backflip and say "Stopeth the riseth!" Then ta-da! The rise will be gone.

I don't want to stop it. I want to minimize it. Too bad I can't use optimization from Calc. I.

[jlftn 11]

big box helps as well as high playing freq.