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X over help

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  • #31
    Within about +/-2dB of a "typical" BSC target (purple line - only about +3dBSC though). 4ohm nominal tweeter section.
    Click image for larger version

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    • #32
      Hey there.

      Not sure anyones still following this thread.

      Got back home and measured some stuff.

      Got good results with active X over using Fab filter and trying to recreate passive version.

      Post some measurements [email protected] 2.83v any input is very welcome there seems to be some strange peaks troughs etc in the response .

      Still no simulation software so pretty much trial and error at the mo . Gonna disregard anything below 200hz as it stands until can improve measurement situation.

      Many thanks for any input .

      Attached Files


      • #33
        One thing that has become apparent to me over the two or so decades I have been playing with this speaker design thing in one form or another, is there will always be people who have to believe that they have achieved a higher plane than everyone else, or absent personal achievement - that there are people not in the conversation who have discovered the grail us mere mortals will never find until we seek the magi.

        FWIW, I think Mr. Paul should run with whatever he comes up with. It is fun, is supposed to be fun, and can be fun as long as the pedants and the magicians do not spend too much time pi$$ing in people's wheaties.

        Disclaimer: read my signature.
        Don't listen to me - I have not sold any $150,000 speakers.


        • #34
          So after a few days experimenting I've ended up here ..........
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          The green is the tweeter out of phase and the db scale is 60 to 90. I think it's worth moving on to building some cabs and tweaking some more.

          I ended up with some pretty weird values for the Cover but they seem to be doing something right.

          I'd like to smooth out the dip from 1.5k ish to 4 if anyone has any ideas about how to go about that.

          Many thanks



          • #35
            I'd add a cap to make the tweeter filter steeper. Possibly reduce the value of the big coil on the woofer a little.

            Maybe use 5dB scales next time if you can.


            • #36
              Where your "sum" (between 3k and 4k) is actually lower than the tweeter level - that means they're out of phase (oop) in that range (not the greatest phase "tracking"). Obviously, flipping the tweeter phase won't fix that ('cause you get a fairly deep "null" then). Your best bet is to step the order(s) of the HP/LP filters up (or down - IF you can, just as rpb has already suggested). Steeper will probably get you to where your headed faster, as it will narrow the band of interaction between the drivers. This is a really good example of one of the reasons why "low order" (like 1ST order) filters are a giant PITA.