Stryke SAE 1204 noise problems

Discussion in 'Archived Threads 2001-2004' started by Jerry Parker, Jan 12, 2002.

  1. Jerry Parker

    Jerry Parker Stunt Coordinator

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    Well I just built a subwoofer using the stryke sae 1204 woofer. Its a 12" woofer with 14mm xmax one way. It is rather similar to the dayton dvc and adire shiva, except it uses a cast aluminum basket, and I believe it has a larger diameter voice coil.

    Anyways, the box I built is 5 cuft downfiring and uses 2 4" diameter ports that are 34 inches long. This should provide a tune around 18hz. Unfortunatly when running sine waves at full volume to the woofer, at 20 and 25hz, you can hear chuffing through the port! I am really surprised because on the stryke website it says to use 1 4" or 3" diameter port!!! I have at least twice their reccomendation, yet I STILL get port noise! What am I doing wrong? Thanks guys
     
  2. Jeffrey Noel

    Jeffrey Noel Screenwriter

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    Jerry, are both ends of your vents flared? If not, it is extremely recommended that your vents be flared. Non-flared vents are usually main culprits of the chuffing noise you mention.
     
  3. Jerry Parker

    Jerry Parker Stunt Coordinator

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    Actually, one end is flared, but not much at all. I guess it isnt even enough to make a difference. Unfortunatly I dont see how I could flare both ends of the ports as they are already installed in the box, and are so long and deep, that I dont think that I can remove them. I guess I have to live with it. It will be downfiring, but isnt right now because I dont have the legs yet. Hopefully that too will help get rid of some port noise. Thanks again.
     
  4. Patrick Sun

    Patrick Sun Studio Mogul

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    34" length of 4" is too long (can lead to pipe resonance). You should aim to keep the port lengths 5-6 times the width of the port.

    I made this mistake once in the construction phase, and on my second try, opted to use a single 6" port 22" long rather than three 4" ports 36" long.
     

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