Misaligned Tempest enclosure

Discussion in 'Home Theater Projects' started by David Judah, Dec 3, 2003.

  1. David Judah

    David Judah Screenwriter

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    Back when I first decided to try my hand at building a DIY sonotube enclosure, about 5 years ago, I built a tube with a ported top cap(6" dia. 19.25" long port). I realized after double checking my math that I made it way too big for the Shiva that I was planning to put into it(it would have been about 222 L), so I put it away thinking I could maybe use it with another driver down the road(I ended up building a whole new sonotube more to my liking because at the time I didn't have a way to cut it down accurately).

    Now, I have a friend who wants to build his own sub but doesn't have the time or ability(so he thinks)to make one from scratch. I was thinking about giving him my old enclosure and with a Tempest all he would have to do is make a bottom cap for the driver, legs and the input cup.

    With the existing port and volume, I get around a 20 Hz tune. Do you guys think the enclosure is too misaligned for a Tempest for him to bother with it as is(I could help him put a longer port in if necessary)? From modeling, GD comes in pretty high down low, but it probably won't be as noticeable for movies. I thought I would get some opinions from the braintrust here because all of the sonotubes and boxes I have built have been for specific alignments.

    What do you guys think?

    Thanks,

    DJ
     
  2. Rob Formica

    Rob Formica Stunt Coordinator

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    I think a tempest would do well in the enclosure... so put it to good use.

    Just the deviations of actual versus theoretical will probably be greater than you existing enclosure is for a particular alignment.

    Rob
     
  3. Kyle Richardson

    Kyle Richardson Screenwriter

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    Tempest will do just fine in 222 liters.
     
  4. David Judah

    David Judah Screenwriter

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    Thanks guys. I'm not worried about the volume, but the tuning with the existing port. It seems kinda high to me(over 20 Hz), but I've been tuning the Tempests from between 15.4 and 18.8 Hz, so that's just been my experience.

    I'll tell him to give it a shot and see how he likes it.

    If it doesn't work out for some reason, I'll have him order an enclosure from you, Kyle.

    DJ
     
  5. Michael R Price

    Michael R Price Screenwriter

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    It works fine. My friend has a 210L Tempest which can be tuned to 21Hz by opening a second port. It might sound a little "heavy" at times but it is not noticeable boomy, it seems more dynamic and powerful sounding. He is using that tune most of the time instead of 15Hz, I believe.
     

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