new type of subwoofer

Discussion in 'Archived Threads 2001-2004' started by Nick L, Jun 13, 2002.

  1. Nick L

    Nick L Second Unit

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    Question: I currently have a down firing subwoofer. I moved into an appartment and was thinking of building a front firing sub. Now my question is, could I build an up firing sub? It would be based on the same concept of a down firing sub only it would fire up? It sounds like it would work, but I'm wondering if the response would be bad since its not bouncing off of the floor. Or would I be better off just going with a front firing sub?

    I'm trying to build a sub to mate with my Boston VRM-50's for music and movies. Will sacrifice movie bass for musicality.

    Thanks for the help

    Nick L
     
  2. terry deto

    terry deto Stunt Coordinator

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    not trying to be a smart a** but wouldn't just be a matter of where you put the feet on the sub box?

    at the least turn you sub so it a down/ front / up and listen to it and compare the sound.
     
  3. Mark Seaton

    Mark Seaton Supporting Actor

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    Terry is mostly right.

    One concern is if the design of a down firing sub used the floor to load the subwoofer with a relatively small spacing. In general this isn't designed for by most DIYers. Up firing would have benefits and detriments. My first comment would be to make sure you have a grille which won't allow any particles or objects to get down to the cone, which would make some very annoying tapping noises. The other option is to have a top plate spaced above the driver.

    I guess the big question is WHY would you want to go up firing? Personally, if possible I always try to conceal an upright, conventional mounting, as then there will never be any concern of driver sag. ANY driver will sag, so says gravity and Newton. The question is only by how much. In some cases it is quite a small number, and with other drivers it can be significant. I believe Adire has a formula to predict this based on the parameters of a driver.
     
  4. Upfiring works just fine...andsame with both=)

    click below=)
     
  5. Neil Joseph

    Neil Joseph Lead Actor

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    There's nothing wrong with a down firing sub as long as the driver has enough room to breathe, which can be achieved by feet or long-enough spikes. Personally, I would go with a front firing sub if it is in a traditional box, or a downfiring sub in a sonotube.
     
  6. Ron D Core

    Ron D Core Stunt Coordinator

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    I made a sonosub with an infinity perfect 10.1 I had laying around. It was ported out the opposite end of the woofer. I noticed no difference in sound between it facing up or down. I left it up just so I could watch it move[​IMG]
     
  7. David_Lew

    David_Lew Stunt Coordinator

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    How many inches do the legs have to be minimum in height for the downfiring sonotube?
     
  8. Robin Smith

    Robin Smith Stunt Coordinator

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    I read in a different post that you should have at least 3" of clearance at the bottom in a down firing config.

    My soon to be finished sonosub has 4.5" legs and a base plate that will sit on the floor.

    Thanks


    Robin Smith
     
  9. Chris Tsutsui

    Chris Tsutsui Screenwriter

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    My legs on my 15" tempest are 5 inches. I didn't know that the feet has an effect on the bass. Should I chop them down to the recommended 4" length?

    Oh, and I'm having trouble with my polyfill, apparently when I demo huge bass tests my two flared ports tend to shoot out small pieces of polyester fiber and my hands arn't small enough to put it back in the ports. I end up using my sister who can reach inside the 3" diameter ports.
     

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