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mid tweeter extention cabinet woes

Discussion in 'Amps and Cabs [BG]' started by Mr DIXOR, Jan 11, 2014.

  1. Mr DIXOR

    Mr DIXOR

    Oct 17, 2013
    I have a CRATE BX-100 with a 15''4ohm internal speaker and an ext.speaker jack wired in seires. I would like to add a small ext. cab with a mid and tweeter and passive crossover,
    but I beleave that the ext speaker is run first and the added cab with crossover affects the sound of the 15'' internal speaker.
    I need proffessionnel help!!
    and so does my project
  2. 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)
    Are you sure that the external jack is wired in series? That would be unusual, and would complicate your plan of adding an external mid/tweet box. There are no off-the-shelf passive crossovers designed for series driver configuration, as far as I know.

    If it turns out that the external jack is in parallel, then you do have the option of adding an external passive crossover in a suitably configured mid/tweet box. You'd only be able to filter the response of the mid and tweet; the woofer would be running full range.

    This can be done with an off-the-shelf passive crossover; Eminence makes such. You might have to modify it a bit if the unused lowpass filter section, which would have been for the woofer, has a capacitor in a parallel leg - you want to cut that connection, as otherwise it can result in an unsafe impedance drop.

    If your goal is to add mids and highs, you'll be successful. If you goal is to end up with a high-end cab on a budget, well that's a long shot without good measurements and a crossover tailored to the specific drivers you're using.
  3. I would do an external brite-box a bit differently.

    Install the 2-way crossover in the brite-box, with an Out jack for LF to the 15".
    This allows the 15 to be used directly as a full-range, or as the Low in a 2-way system with the brite-box.

    Difficulties come with the 4-ohm Low driver.
    (Most) COTS crossovers won't work, as they are designed for 8-ohm loads.
    Custom passive networks are Expen$ive for the components...

    All the above is why I biamp. Easier. Cleaner. No match problems.
    My current ProLite2 has a 100 Hz, 4th order crossover built in.
  4. bobcruz


    Mar 10, 2004
    Alameda, CA
    In their latest sales catalog, PartsExpress had a bunch of cheap two-way crossovers that could switch between 4 and 8 ohms for the woofer. Cheap because they were a manufacturer's error and the crossover points came out to be something unusual but not unreasonable like 2700 Hz. Did I mention they were cheap? ;)