Results 1 to 5 of 5

Thread: DIY Tweeter horns - 2404 based?

  1. #1
    Member
    Join Date
    Sep 2004
    Location
    Australia
    Posts
    98

    DIY Tweeter horns - 2404 based?

    I currently have 2405's but think that it would be better to have tweeeters whose directivity was more constant with frequency.
    I want approx. 1 radian horizontal and .67 vertical (60 x 40 for the metrically impaired).
    I have examined a dismantled 2404 and it looks reasonably easy to keep the back 2/3 and just replace the plastic "baby butt" with a new home made horn - any one here tried this?
    The current horn preference is for a short exponential transition to a more or less parallel sided pyramidal horn ("conical" expansion rate)
    - any one here tried this horn shape?

    TIA

  2. #2
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,170
    Hmm that's an idea doesn't sound easy though to make it really work well. Black magic to me! Just a thought the 076 had an eliptical horn. Maybe that would work as a stating point. Problem is I don't know what the coverage is and have never seen a spec sheet to cover it.


    Rob
    Attached Images Attached Images  

  3. #3
    RIP 2011 Zilch's Avatar
    Join Date
    Jun 2004
    Location
    Berkeley, CA
    Posts
    9,963
    076 is a good suggestion, but finding them's another matter. Member Steve Gonzales loaded 076 horns on 2404 motors with apparent success recently.

    2405 is not far off from what you're wanting, actually:

    Dispersion (6 dB down points, 1/3-octave band, pink noise):

    140° horizontal x 40° vertical at 10 kHz
    90° horizontal x 35° vertical at I6 kHz
    65° horizontal x 30° vertical at 20 kHz

    If that's too "beamy" for your preference, I'd just go directly to 2404.

    OR look at what JBL does for UHF in some of their 60 x 40 controlled directivity offerings, if anything....

  4. #4
    Alex Lancaster
    Guest
    I have looked at factory specs for over 25 Years, still the 2405 sounds better to me; ???-

  5. #5
    ralphs99
    Guest
    Hi Dave,

    I’m wondering what you mean by wanting constant directivity. As I’m sure you know a CD horn has a similar polar response with varying frequency. So for a horn to exhibit constant directivity, it must cover a reasonably wide frequency range. ie you could measure polar response at 1/2 octave centre frequencies to see how constant the directivity appears. (Have a look at the directivity index graphs for the 2344). As the 2405 only covers one-and-a-bit octaves, the concept of constant directivity is less meaningful than for a midrange horn that covers several octaves. I personally think it is sufficient to simply match the approximate polar response of the tweeter in the horizontal plane with the polar response of your mid-range device. As the polar response of a 2404 and 2405 are similar in the horizontal plane, ~100 degrees at 15kHz as Zilch pointed out, I feel there will be little benefit in switching to a 2404. Having said that, you may simply prefer the sound of the 2404 or need the extra dispersion in the vertical plane.
    Maybe you fill us in on the rest of your system….

    Cheers,
    Ralph.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. List of JBL info
    By Donald in forum Lansing Product General Information
    Replies: 3
    Last Post: 10-27-2004, 04:17 AM
  2. Crossovers for K2S9800 and/or S1M, tweeter over 1,5"driver
    By sebackman in forum Lansing Product Technical Help
    Replies: 7
    Last Post: 02-16-2004, 02:38 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •