Port Length

Discussion in 'Archived Threads 2001-2004' started by Will Pomeroy, May 15, 2002.

  1. Will Pomeroy

    Will Pomeroy Stunt Coordinator

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    If I were to build a ported tempest in a 142L enclosure, how long would, and how big would I want to make my ports? I do not want to spend money of flared vent kit, and I definetly don't want any wind noise. What tunning frequency should I am for? What would be the best port diameter?

    Thanks very much,

    Will.
     
  2. Greg Monfort

    Greg Monfort Supporting Actor

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    Frankly, if the sim is to be believed (and FWIW I believe it [​IMG]), you're better off leaving it sealed at this Vb, so no vent noise. [​IMG] There really is no viable tuning frequency with a low vent mach without using a PR and you're only losing a couple of dB down really low where your hearing acuity can't tell the difference. Also, transient response will be better, though I can't say how audible it may be.
    GM
     
  3. Dave Poehlman

    Dave Poehlman Producer

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    I would have to agree with Greg here. Just plugging the Tempest specs into ISD online you would need to tune your port to maybe 15Hz or so to avoid boomy-ness (a wide hump just before the low-end rolloff). But, then you are looking at a longer port. On top of that, your rolloff begins to look a lot like a sealed box anyway.
     

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