More dead/fried Tumults

Discussion in 'Home Theater Projects' started by Seth_L, Apr 27, 2003.

  1. Seth_L

    Seth_L Screenwriter

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    http://forums.acoustic-visions.com/i...t=ST&f=4&t=487

    Details are still somewhat sketchy on this one, but it's pretty crazy that in less than 20 seconds Jeff was able to fry one of his Tumults. He has two. Each was powered from a bridged K2 and they're in 5 cu-ft PR enclosures. He also apparently fried his 2nd one, but he hasn't given any details on how long that took.

    It's my understanding that VC's fry/melt from heat. I find it rather hard to believe he was able to overheat a voice coil within 20 seconds.

    Seth
     
  2. Chris Carswell

    Chris Carswell Supporting Actor

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    Someone else here fried one as well.....
     
  3. Allen Ross

    Allen Ross Supporting Actor

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    ouch, i would be really POed a grand gone in 20 sec, damn, i know my limits of my tempest, and i all ways watch the BFD for clipping so i hopfully won't blow mine
     
  4. Michael R Price

    Michael R Price Screenwriter

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    I can understand how it might be hard to detect distortion when the voice coil nears its thermal limits. But unless this happened at a very high level, the driver could have been defective. That would also be understandable. But, I'm guessing Jeff just didn't realize how much sound he was getting. I'm not sure what Adire should do about this.
     
  5. Sad story. sorry to hear.

    I think the biggest warning is this. XBL2 DOES NOT distort like traditional drivers. Speaking from experience, there is much less distortion in the low frequencies than typical drivers. This makes them seem "quieter" than conventional motors that typically have much higher distortion levels at those frequencies.

    One thing to note. In every fried tumult, they were powered with a K2 bridged PER SPEAKER. The K2 puts out a REAL 2500watts RMS this way. this is CONSIDERABLY over the spec.
     
  6. Craig Woodhall

    Craig Woodhall Supporting Actor

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    yip, i wouldn't put that much power into my box.. im running mine at about 800w, it gets incredible bass and never near its limit.. i think a K2 for a pair of Tumults, not bridged per Tumult, that's crazy..

    Craig
     
  7. Pete Mazz

    Pete Mazz Supporting Actor

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    He goes on to say he was playing them loudly and then cranking them up louder for periods of 20 seconds....

    Pete
     
  8. Cam S

    Cam S Screenwriter

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    Hmmmm, I don't think this is the subwoofers fault? Seems pretty crazy going that much over the limit of the sub and driving it that hard.
     
  9. Brian Bunge

    Brian Bunge Producer

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  10. John Wes

    John Wes Stunt Coordinator

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    I'll bet your skin vibrates faster than a go fast rice burner for that 20 seconds though...
     
  11. Chris Carswell

    Chris Carswell Supporting Actor

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    Brian, I excluded the persons name to protect their identity as well as for the sake of ALL past, present, & future idiots across the board......... [​IMG]

    BTW - did you get that email I sent a bit back?
     
  12. Brian Bunge

    Brian Bunge Producer

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    Chris,

    Thanks. I'll take all the protection I can get. Even if it's from down south![​IMG] I remember getting an email from you. Did I not reply?
     
  13. Chris Carswell

    Chris Carswell Supporting Actor

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    "Did I not reply?"

    Nope, no reply [​IMG] I thought you were being spiteful b/c we have a better football program [​IMG]

    I think it was more about the mic/pre stuff & some about the AV15.
     
  14. Brian Bunge

    Brian Bunge Producer

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    Chris,

    I could give a rat's ass about college ball. My pro team is even further down south from you. [​IMG]
     
  15. Chris Carswell

    Chris Carswell Supporting Actor

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    What?!?!?!?!?!?!?!?
    You know you are a Red Skins fan Brian. Even more now since they got that new bad ass coach. [​IMG]

    (OK Seth_L, I'm done poking at Brian. I'll stop hijacking your post now)
     
  16. Hank Frankenberg

    Hank Frankenberg Cinematographer

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    Who can tell, but when we find out, the admins should post his story on this forum as THE example of how not to test a new driver. [​IMG]
     
  17. Patrick Sun

    Patrick Sun Moderator
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    I can make it a stickey post. [​IMG]
     
  18. Seth_L

    Seth_L Screenwriter

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    I posted this at Acoustic-Vision's forum, but I'll post it here since it's pretty important.

    The Tumult is rated 1600W RMS. I like most people assumed this was an RMS rating meaning I needed an amp that could put out 1600W+. Well the secret is that 1600W per IEC 268-5 dicatates that the driver only be able to withstand that power for 1 second.

    I recall reading that some sub makers plug their subs in a 120V wall socket for torture testing, or for SPL burping. Some of them could withstand minutes of a wall socket and work fine.

    Now the Tumult is supposed to be the baddest of the bad, the driver to destroy all drivers, but it clearly doesn't have the power handling capability of most of the other drivers in it's class.

    What good is all that excursion if you can't put enough power to use it without frying the drivers?

    Seth
     
  19. Kyle Richardson

    Kyle Richardson Screenwriter

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    See my post on the AV forum regarding Seth's post. If one looks at the specs it clearly shows Pmax in which most DIYers know is maximum power handling not RMS.

    As Tony said, the bridged K2 puts out 2500 watts which is 900 Watts ABOVE MAXIMUM power handling.

     
  20. Seth_L

    Seth_L Screenwriter

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    Kyle,

    The IEC 268-5 number is supposed to be a RMS number. It's a Root Mean Squared measurement of max power. You're trying to suggest it's a peak number and by definition it is not. The peak should be 1.41421 times as high. That means a Tumult should take a peak (not RMS) power of 2262.74W.

    There is not a sustained RMS rating on the sub. I'd like to see one. Considering Dan recommended 1000+ watt amps to drive it... I would assume (perhaps incorrectly) that a Tumult should be able to withstand sustained (longer than 1 second) use of 1000+ watts.

    We have no proof that Jeff used all 2500W of his amp to destroy his tumults. It's possible, but we don't know. He could have just have easily blown one with a 1600W RMS amp because he could still exceed the Pmax (the way it is defined).

    What is a safe "max" RMS value for an amp to be connected to a Tumult? 800W? 1000W? 1200W?

    Seth
     

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