LDS 1-12s: Houston, We Have A Problem!

Discussion in 'Amps and Cabs [BG]' started by ::::BASSIST::::, Sep 4, 2010.

  1. ::::BASSIST::::

    ::::BASSIST:::: Progress Not Perfection.

    Sep 2, 2004
    Vancouver, BC Canada
    Not hiding anything Louise. I just wanted to confirm what my ears were telling me before I disclosed any info on the LDS cabs. However, once I had played them in a number of rooms I knew something was up. That's when I did a very close inspection/listen and found out what the issue was.

    I actually just a bought a schroeder 1212BMF and once that arrives in a few weeks, my UL112 will be up for sale again. I still have my 15/6 for gigs, but I'd rather use the UL112 for rehearsals until the 1212bmf arrives.
  2. loopee

    loopee Supporting Member

    May 12, 2009
    Surrey, B.C. Canada
    Not at all implying you were "hiding" anything Torin, just simply understanding why you were reticent to write a review so I figured something was not as it should long as Don can fix it all should be well I'm still interested in the UL112 so let me know when it's up for it turns out I'll have 3 choices at/or about the same price for all 3......1) GK Neo 112-II 2) Traynor TC112 3) Your UL112 and I'll be trying out both the Traynor and the GK sometime this week and should know by then what I'll be buying
  3. I had a similar problem with some 1X18 DIY cabinets with 4" ports. I used a router to flare the front and back of the port tube and the chuffing went away.

  4. ::::BASSIST::::

    ::::BASSIST:::: Progress Not Perfection.

    Sep 2, 2004
    Vancouver, BC Canada
    What do you mean by 'flare' ???
  5. Mike Shevlin

    Mike Shevlin

    Feb 16, 2005
    Las Vegas
    ^Can't wait to hear your review of the 1212bmf
  6. The ends of the port tubes are normally flush with the baffle. I used a router to shape the edges to look like a horn flare. They can be purchased commercially but look a little different like in the image below. The same effect can be accomplished with the existing port tubes with a router.


  7. DukeLeJeune

    DukeLeJeune rational romantic mystic cynical idealist Supporting Member Commercial User

    Nov 24, 2008
    Princeton, Texas
    Owner & designer, AudioKinesis; Auth. mfg, Big E (Home Audio only)
    Flaring the ends of the port helps significantly as far as chuffing goes. Turbulence at the ends of the port, in particular the inside end, is what causes chuffing; it's a fluid flow issue, and the fluid is air. The flares facilitate smooth airflow at the ends of the port, allowing a smaller diameter port to be used before chuffing sets in. In a conversation with an engineer at Eminence, he told me that for a particular application a 4" port was needed, but when I told him I was using Precision Ports (like in the image gbarchus posted) he said that a 3" diameter Precision Port would work fine.