Downside of subs in front corners??

Discussion in 'Archived Threads 2001-2004' started by John Cain, Jan 23, 2002.

  1. John Cain

    John Cain Second Unit

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    I have a SVS CS-Ultra aub.

    I'm thinking of getting another one.

    What is the downside of having subs in both front corners of the room??

    What are the advantages?? I'm guessing one advantage might be more bass at all seats??

    -- John
     
  2. Greg_R

    Greg_R Screenwriter

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    Putting another identical sub in the other front corner will give you a 3dB increase in (perceived) SPL. Putting it in the same corner will give you a 6dB increase. Not placing the subs together will result in phase cancelations at various frequencies / room locations. If possible I'd put them both in the same corner and EQ appropriately (eliminate room modes, etc.)...
     
  3. Tom Vodhanel

    Tom Vodhanel Cinematographer

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    The amount gained by using adjacent corners will depend on the distance between the subs. In most cases...it will be 3-4.5dBs. As noted, it's usually best to use the same corner for both...but using adjacent corners can be a very good alternative.

    TV
     
  4. Richard Greene

    Richard Greene Stunt Coordinator

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    Using subs in adjacent corners sacrifices 1 to 3dB bass output due to destructive interference (cancellation).

    Using two subs makes the subs easier to integrate with the left and right main speakers (two subs form a phantom center image) when there is too much output above 80Hz.

    and the subs are NOT sonically invisible.

    The stereo image is almost entirely from output OVER 80Hz. Using one sub and sharply limiting output over 80Hz. is a better solution, in my opinion.

    When you place subs in the left and right front corners, they energize the standing wave between the side walls out of phase which cancels the standing wave and gives you a hole in the bass frequency response at that standing wave frequency. Unlike a standing wave peak whose SPL can be reduced with an equalizer, you can't equalize away the cancellation caused by two subs on opposite ends of the room. If that side-wall-to-side wall standing wave is annoying when you use one subwoofer, I suppose using a second subwoofer on the opposite side of the room is one way to fight a standing wave. But buying an equalizer and is a cheaper and better solution, in my opinion .
     
  5. KevinGS

    KevinGS Stunt Coordinator

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    What about putting a sub in each diagonally opposed corner in a room 10.5 x 27 x 7.5?

    thx

    kev
     
  6. Tom Vodhanel

    Tom Vodhanel Cinematographer

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    I think that would be the worse scenario,(dia-corners).

    TV
     
  7. ling_w

    ling_w Second Unit

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