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Eden D115T - and other rear ported cabs - leave room in back?

Discussion in 'Amps and Cabs [BG]' started by peteroberts, Jul 5, 2005.


  1. Happy 4th fellow Americans! Everyone else, hello!

    I have a question about the subject cab and others like it (it has a rear port that's kinda small maybe 6"?)

    Is there a minimum distance that you want the cab from the wall? It really seemed to open up when I gave it 2 feet...but I wasn't comparing in the same room...how much of a difference does it make in your sound when you're 'backed up against the wall' vs. having all the room you want in back of the cab?
     
  2. tornadobass

    tornadobass Supporting Member

    Nov 20, 2000
    Iowa City, Iowa
    Endorsing Artist: Black Diamond & SuperSensitive strings
    There seems to be a lot of opinions on this...my feeling is that stage space is usually limited and 2' would be impossible in many cases. My goal is to shoot for about 4 to 6 inches, enough to let the sound out without taking up too much stage space.
     
  3. Brad Johnson

    Brad Johnson Commercial User

    Mar 8, 2000
    Gaithersburg, Md
    Boom Bass Cabinets, DR strings
    With limited stage space you can angle the cab.
     
  4. pickles

    pickles Supporting Member

    Mar 23, 2000
    Ventura, CA
    Depends on the room. Sometimes you want that rear port boom, and sometimes you really need to get the cab close to a wall to control it. They're a little more finikey than front ported cabs in that way. That back of the room rumble can ruin a mix if you're not careful.
     
  5. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    Beware the Allison effect. That's the cancellation of your signal when the sound bouncing off the rear wall reunites with the sound from your speakers at 180 degrees out of phase when the distance from the speakers to the wall is 1/4 wavelength. Two feet is 1/4 wavelength at 141 Hz. Three feet is 94 Hz. With rear port it's less problematic, as the port is closer to the wall and the frequencies coming from it pretty much limited to less than 100 Hz. Generally you want the front of your cab either less than 2 feet or more than six feet from a wall or you will have a response hole somewhere in the middle of your power band.
     

  6. Thanks so much Bill. Succinctly put!
     
  7. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    Whatever you do, don't obstruct the port.