non-flared port

Discussion in 'Home Theater Projects' started by bernard&*, Apr 27, 2004.

  1. bernard&*

    bernard&* Stunt Coordinator

    Joined:
    Mar 1, 2004
    Messages:
    56
    Likes Received:
    0
    I'm going to build my first diy sub sooner.Is there any big diff. in performance, if i used a non-flared port tube(like PVC pipe) rather than flared one.
    [​IMG]
     
  2. DarrenHo

    DarrenHo Stunt Coordinator

    Joined:
    Feb 20, 2004
    Messages:
    127
    Likes Received:
    0
    i imagine you might see more port noise with the non flared port. try it out. you could always go to a flared one later if it proves a problem.
     
  3. Jeremy Stockwell

    Jeremy Stockwell Supporting Actor

    Joined:
    Aug 9, 2001
    Messages:
    608
    Likes Received:
    0
    Bernard,

    If you can provide some details about your project, you'll get better responses.

    If you're talking about venting a Tempest with a single 3" non-flared port, than you'll probably have problems. If you're talking about venting a Tempest with a 6" non-flared port, then you're probably OK.

    The flares definitely help to prevent port noise, but are sometimes not necessary depending on your specific situation.

    JKS
     
  4. bernard&*

    bernard&* Stunt Coordinator

    Joined:
    Mar 1, 2004
    Messages:
    56
    Likes Received:
    0
    jeremy,
    I'll go with the tempest, adire alignment with vented FP3 3"flared port kits with 11"center tube.(cost to much) if there will be no big problem using pvc pipe I'll go with it.BTW I'll change the box size but stick to its volume 214L. I worked with Winisd in 214L, 20"Wx24"Hx34"D, I just add 1"(0.93)for the offset measurement of Winisd with respect to adire recommend(legs not included).Please help me with this calculation.[​IMG] any way thanks for reply.
     
  5. GrahamT

    GrahamT Supporting Actor

    Joined:
    Sep 13, 2003
    Messages:
    556
    Likes Received:
    0
    I tried the Tempest with 2 3" PVC and I did get port noise, the flared ports are much better
     
  6. Jeremy Stockwell

    Jeremy Stockwell Supporting Actor

    Joined:
    Aug 9, 2001
    Messages:
    608
    Likes Received:
    0
    FWIW, I've got a Tempest in 290L tuned to 17.5Hz with a 6" PVC (non-flared). I don't get any port noise in its operational range.

    JKS
     
  7. Aaron Howell

    Aaron Howell Stunt Coordinator

    Joined:
    Nov 19, 2003
    Messages:
    196
    Likes Received:
    0
    After all the money, time, and effort you put into the box the $20 for the port will seem minimal when you hear the port noise. Been there, done that.
     
  8. bernard&*

    bernard&* Stunt Coordinator

    Joined:
    Mar 1, 2004
    Messages:
    56
    Likes Received:
    0
    Hi! Aaron,
    I think your right I'll go for the flared port.
     
  9. Bhavesh

    Bhavesh Stunt Coordinator

    Joined:
    Nov 27, 2003
    Messages:
    60
    Likes Received:
    0
    bernard&*,
    you can buy the flared port and terminals much cheaper at Parts Express.
     
  10. Stephen Hopkins

    Stephen Hopkins HW Reviewer
    HW Reviewer

    Joined:
    Jul 19, 2002
    Messages:
    2,598
    Likes Received:
    0
    PE also has some buy-out 3" flared ports dirt cheap, but they're only available in 9" and 11.5" lengths that aren't adjustable like the precision flared ports.

    Another way to get flared ports using strait PVC is to mount the pipe on a double thick wall of MDF (you'll probably want to double up on the baffle anyway) and then use a flush cut router bit to cut the hole then a big 1/2" round-over bit for the flare. Also gives the port a very flush look since it's actually part of the wood and not just a piece of plastic mounted to it.

    Hope this helps [​IMG]
     
  11. Owen Bartley

    Owen Bartley Second Unit

    Joined:
    Nov 11, 2002
    Messages:
    487
    Likes Received:
    0
    Bernard, I have a 5.5" non flared port in my Tempest and haven't heard port noise yet.

    Try out Adire's version of LSPcad, they have a measurement for air speed at the port, which should give you a decent indication I think.
     
  12. Justin Ward

    Justin Ward Supporting Actor

    Joined:
    Jun 6, 2002
    Messages:
    673
    Likes Received:
    0
    I've got two 3" non-flared in my SBB4 Tempest. I only notice port noise when playing test tones near the tuning point at loud volume.
     

Share This Page