Obi's IB

Discussion in 'Archived Threads 2001-2004' started by Robert George, Apr 4, 2002.

  1. Robert George

    Robert George Screenwriter

    Joined:
    Jul 3, 1997
    Messages:
    1,089
    Likes Received:
    65
    Better late than never. I promised pics of my infinite baffle sub install and here they are...
    Obi's IB
    I'll also post a link in the "speakers and subwoofers" section where I will discuss any performance aspects of the install anyone is curious about.
     
  2. Cam S

    Cam S Screenwriter

    Joined:
    Jan 11, 2002
    Messages:
    1,524
    Likes Received:
    0
    Wow, very nice work. I love how it looks with those nice SVS subs peaking out from the wall. What are the power ratings of the Sumo amp, that thing is massive!!!

    BTW, how does it sound???
     
  3. Robert George

    Robert George Screenwriter

    Joined:
    Jul 3, 1997
    Messages:
    1,089
    Likes Received:
    65
    Yeah, I like the looks of the drivers myself. I thought about a grill to cover them, but I think I'll keep them "uncovered" for now.

    The Sumo is rated at 260 wpc into 8 ohms and over 400 wpc into 4 ohms (these are 4 ohm drivers). An IB is inherently more efficient than a traditional box sub, so I have power to spare here.

    How does it sound?

    Amazingly good. Very tight. Very quick. Seamless blend with the mains. Really, the best overall bass I have ever heard. Some subs go lower and some play louder, but none I have heard do everything as well as this design.
     
  4. rodneyH

    rodneyH Supporting Actor

    Joined:
    May 22, 2001
    Messages:
    844
    Likes Received:
    0
    let me see If I understand the concept correctly, simply mount a sub or 2 or 4 or 8 in a wall, separating the front from the rear and "walla" you have a great sounding sub?? do you need to do any calculations for the area behind it?? etc...

    seems to me that if this is truely a great sounding sub, this IB idea sounds great (less floor space, increased WAF, decreased cost, increased efficiency and volume, am I missing any??)
     
  5. Cam S

    Cam S Screenwriter

    Joined:
    Jan 11, 2002
    Messages:
    1,524
    Likes Received:
    0
    the IB design seems almost too good to be true, I mean you can't design it like you can a normal sub box with LSPcad and WinISD.
     
  6. Mike Knapp

    Mike Knapp Supporting Actor

    Joined:
    Aug 4, 1997
    Messages:
    644
    Likes Received:
    20
    Real Name:
    Mike
    I just know your front soundstage improved dramatically with the removal of the tubes from the right side of the room. I cant wait to actually hear it.
    This is one of those win-win DIY situations. If you have the room to do one (attic space, basement or closet), you will not find an easier (no cabinetry involved), better sounding bass arrangement. The icing is the WAF which is extremely high.
    Congratulations on the completion of the install. I am jealous because I have not yet figured a way to do one in my room, even though I have been longing for one since I heard Rich Kraus' install last year.
    Now....just one more suggestion [​IMG]
    If you paint the wall (yes the whole wall) behind the speakers black, that image on your TV will improve dramatically (no matter how good it already is)! I promise you it will be night and day different. The contrast will be perfect and when you watch a movie at night, all you see is screen. If you cant get away with black, pick a really dark accent color.
    Remember when you were down here you were commenting on the great contrast I was getting in the Mits? It is the black surrounding wall that does it. If you decide to try this I will deny I suggested it when your Mrs. asks me! [​IMG]
    Mike
     
  7. Pete Mazz

    Pete Mazz Supporting Actor

    Joined:
    May 17, 2000
    Messages:
    761
    Likes Received:
    0
    Looks good, Obi!

    Any problem with the location being so close to the RPTV?

    Pete
     
  8. Rich Kraus

    Rich Kraus Stunt Coordinator

    Joined:
    May 3, 2000
    Messages:
    209
    Likes Received:
    0
    very sweet obi.
    i wish i had a deep enough room to flush "the stuff" into the wall like you have done. maby when i find that big bag of money on the side of the road and buy another house. [​IMG]
    yup IMO, you cant beat these IB's on many fronts. Mike calls the SAF on these icing on the cake, but for me it makes bass like this even possible. My spouse wold have long ago veto'd a large box. I HAD to find another way. turns out the other way works pretty good. [​IMG]
     
  9. ThomasW

    ThomasW Cinematographer

    Joined:
    Nov 6, 1999
    Messages:
    2,282
    Likes Received:
    0
    Obi
    Looks good [​IMG]
    I'll add your pics and a link to your site to the IB gallery
    Enjoy [​IMG]
    Cam S.
    If you want to model an IB, just use a box size that's 10 times larger than the total Vas of all the drivers
     
  10. ColinM

    ColinM Cinematographer

    Joined:
    Dec 9, 2001
    Messages:
    2,050
    Likes Received:
    0
    My question is this - Often you have to move a sub around the room to find the best location...how do you approach this with an IB? Would you assume that the optimum position with a traditional sub would be the best for the IB as well? If I had to cut a hole in the wall or ceiling, this is the one issue that would keep me up at night.

    TIA -

    - C

    PS - Beautiful job and components!
     
  11. ThomasW

    ThomasW Cinematographer

    Joined:
    Nov 6, 1999
    Messages:
    2,282
    Likes Received:
    0
  12. ColinM

    ColinM Cinematographer

    Joined:
    Dec 9, 2001
    Messages:
    2,050
    Likes Received:
    0
    TYVM!
    [​IMG]
     
  13. Chad Isaacs

    Chad Isaacs Supporting Actor

    Joined:
    Feb 20, 2000
    Messages:
    757
    Likes Received:
    0
    I need...er um..want one now.
     
  14. Robert George

    Robert George Screenwriter

    Joined:
    Jul 3, 1997
    Messages:
    1,089
    Likes Received:
    65
     
  15. jeff lam

    jeff lam Screenwriter

    Joined:
    Jun 4, 2001
    Messages:
    1,798
    Likes Received:
    0
    Location:
    San Jose, CA
    Real Name:
    Jeff Lam
    I thought an IB needed some type of enclosure. From the pics, it looks like it is mounted in the wall dividing two rooms. How is this different than just "Free Air"?
     
  16. Rick Guynn

    Rick Guynn Second Unit

    Joined:
    Mar 23, 1999
    Messages:
    473
    Likes Received:
    0
    The difference is that 'free-air' has no partition and the front and back waves may intermingle and cancel each other out. An IB separates the front and back waves so there is no cancellation...
     
  17. jeff lam

    jeff lam Screenwriter

    Joined:
    Jun 4, 2001
    Messages:
    1,798
    Likes Received:
    0
    Location:
    San Jose, CA
    Real Name:
    Jeff Lam
    So an IB front has to be totally isolated from the IB back? Like a Bandpass design...just bigger?
     
  18. Brian Bunge

    Brian Bunge Producer

    Joined:
    Sep 11, 2000
    Messages:
    3,716
    Likes Received:
    0
    Jeff,

    No, like a huge sealed enclosure.
     
  19. ThomasW

    ThomasW Cinematographer

    Joined:
    Nov 6, 1999
    Messages:
    2,282
    Likes Received:
    0
    jeff

    Thankfully an IB is nothing like a bandpass.

    It's really a sealed box that just happens to be huge. Hence the name 'infinite baffle'
     
  20. jeff lam

    jeff lam Screenwriter

    Joined:
    Jun 4, 2001
    Messages:
    1,798
    Likes Received:
    0
    Location:
    San Jose, CA
    Real Name:
    Jeff Lam
    so do you have to worry about air leaks? I just don't understand how such a large enclosure can be effective. I guess I'll have to study up on IB designs. The design never really caught my interest till now.
     

Share This Page