Announcement

Collapse
No announcement yet.

New waveguide with vifa OC25SC65-04

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • New waveguide with vifa OC25SC65-04

    Today I altered a waveguide that TN Allen made for me a while back. The tweeter is a flangeless vifa. http://www.parts-express.com/pe/show...umber=264-1018

    I had to hold the tweeter in the waveguide by hand. Off axis measurements angles are approximately 30, 45, and 60 degrees. The on axis is the one with the distortion shown. All measurements are with a x-over consisting of one cap, and one coil. The distortion below 2k is actually lower than it appears to be here. This tweeter will probably be crossed at 3k.

    Edit...I don't know why, but now I measure a dip on axis at 7k. The only difference I know of is that now I have a piece of wood holding the tweeter in the guide. It's possible that the location has changed very slightly. Off axis still looks about the same though.
    Last edited by rpb; 07-07-2013, 11:41 AM.

  • #2
    Re: New waveguide with vifa OC25SC65-04

    Nice, got a pic of the waveguide?
    Kenny

    http://www.diy-ny.com/
    DIY NY/NJ 2014 https://www.youtube.com/watch?v=FGwA...ature=youtu.be
    Man does not live by measurements alone, a little music helps.

    Comment


    • #3
      Re: New waveguide with vifa OC25SC65-04

      Here's the distortion with a filter that allows the response to go lower. Note that at 1.5k, it's -70 dB.
      Attached Files

      Comment


      • #4
        Re: New waveguide with vifa OC25SC65-04

        Can you make this on TN Allen's new jig?
        Kenny

        http://www.diy-ny.com/
        DIY NY/NJ 2014 https://www.youtube.com/watch?v=FGwA...ature=youtu.be
        Man does not live by measurements alone, a little music helps.

        Comment


        • #5
          Re: New waveguide with vifa OC25SC65-04

          Sweet
          " To me, the soundstage presentation is more about phase and distortion and less about size. However, when you talk about bass extension, there's no replacement for displacement". Tyger23. 4.2015

          Quote Originally Posted by hongrn. Oct 2014
          Do you realize that being an American is like winning the biggest jackpot ever??

          http://www.midwestaudioclub.com/spot...owell-simpson/
          http://s413.photobucket.com/albums/pp216/arlis/

          Comment


          • #6
            Re: New waveguide with vifa OC25SC65-04

            Originally posted by kenny_k View Post
            Can you make this on TN Allen's new jig?
            It's very simple, but part of the guide is flat. TN Allen and I are working on a new guide that is similar to this one. It has a constant radius of about 6", and could likely be made with his jig. This one was altered. I cut the depth back about half an inch. There's a lot of body filler in it. I hand sanded it. It should be relatively easy to duplicate. I think the Vifa is responsible for most of the performance.

            Comment


            • #7
              Re: New waveguide with vifa OC25SC65-04

              Here's a picture. It's about 6".
              Attached Files

              Comment


              • #8
                Re: New waveguide with vifa OC25SC65-04

                Looks BIG. Can you use it to cast other waveguides?
                Kenny

                http://www.diy-ny.com/
                DIY NY/NJ 2014 https://www.youtube.com/watch?v=FGwA...ature=youtu.be
                Man does not live by measurements alone, a little music helps.

                Comment


                • #9
                  Re: New waveguide with vifa OC25SC65-04

                  Originally posted by kenny_k View Post
                  Looks BIG. Can you use it to cast other waveguides?
                  It was cut out of a thick piece of wood. The back side was cut away with a router, and a new piece of wood inserted. Then I added body filler, and sanded it. This would be easy to make.

                  Comment


                  • #10
                    Re: New waveguide with vifa OC25SC65-04

                    Post a pic with the tweeter in the opening. I'm curious about where the dome sits relative to the opening.
                    R = h/(2*pi*m*c) and don't you forget it! || Periodic Table as redrawn by Marshall Freerks and Ignatius Schumacher || King Crimson Radio
                    Byzantium Project & Build Thread || MiniByzy Build Thread || 3 x Peerless 850439 HDS 3-way || 8" 2-way - RS28A/B&C8BG51

                    95% of Climate Models Agree: The Observations Must be Wrong
                    "Gravitational systems are the ashes of prior electrical systems.". - Hannes Alfven, Nobel Laureate, Plasma physicist.

                    Comment


                    • #11
                      Re: New waveguide with vifa OC25SC65-04

                      I posted this too quickly. I still think the vifa will be a good candidate for a waveguide, but this guide is not as good on axis as I originally measured. I really don't know why the measurements changed.

                      Comment

                      Working...
                      X