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Frequency response help?

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  • #16
    Re: Frequency response help?

    I looked at the setting on the receiver, and the room correction was turned on. The receiver said the right speaker wiring was 'reversed'.

    I turned all of the room correction settings off and remeasured. Here are the results.

    Left side no processing/EQ Click image for larger version

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    Right side no processing/EQ Click image for larger version

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    I'm thinking the differences between the left and right channels is the stuffing. I didn't measure out the stuffing so I don't think equal amounts of stuffing went into the speakers. I'm going to remove the stuffing and remeasure.

    So while I've got the speakers open, should I reverse the polarity of the tweeter? Should I do this for both, or just the right one (since the receiver said it was wired 'backwards').

    Thanks again everyone for the help!

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    • #17
      Re: Frequency response help?

      Originally posted by Jeff B. View Post
      That would most likely be caused by the electronics that the sweep is being played through. I have never had a plot that was falling at the top unless that was the actual response of the driver.

      I also don't like all of this smoothing either, but I guess that's just me.
      I copied the CD to the hard drive of my PS3. I played the test tracks from my PS3 sent via HDMI to my Yamaha Aventage RX-A3000 receiver. Maybe I'll try playing the CD from my Xbox 360.

      You mentioned smoothing, what is the best smoothing to test the frequency response at? This test was done at 1/6 smoothing.

      Thanks again.

      Comment


      • #18
        Re: Frequency response help?

        Originally posted by lucasa.miller View Post
        I copied the CD to the hard drive of my PS3. I played the test tracks from my PS3 sent via HDMI to my Yamaha Aventage RX-A3000 receiver. Maybe I'll try playing the CD from my Xbox 360.

        You mentioned smoothing, what is the best smoothing to test the frequency response at? This test was done at 1/6 smoothing.

        Thanks again.
        I always take my measurements at 1/48th oct smoothing. But that's just my choice. This way I can see what's really happening.
        Click here for Jeff Bagby's Loudspeaker Design Software

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        • #19
          Re: Frequency response help?

          Where the room starts kicking in, both speakers are fairly similar. I am guessing if you looked around, you would see both of them are not equidistant from all reflective surfaces.

          It looks like the tweeter is over-padded quite a bit as well.
          Don't listen to me - I have not sold any $150,000 speakers.

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          • #20
            Re: Frequency response help?

            Originally posted by Jeff B. View Post
            That would most likely be caused by the electronics that the sweep is being played through. I have never had a plot that was falling at the top unless that was the actual response of the driver.

            I also don't like all of this smoothing either, but I guess that's just me.
            I also experienced falling off at around 13K. Still haven't determined the cause. i almost wondering if it can be baffle related.

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            • #21
              Re: Frequency response help?

              Originally posted by jimbones View Post
              I also experienced falling off at around 13K. Still haven't determined the cause. i almost wondering if it can be baffle related.
              ? I cannot see how it can be caused by the baffle.
              Click here for Jeff Bagby's Loudspeaker Design Software

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              • #22
                Re: Frequency response help?

                Just gave it another quick look, and it looks more and more like the crossover is far from optimal for this design. While I will readily admit the room could be influencing it heavily, I still see some things I do not like. The tweeter is pretty low in output, and the crossover region is depressed, and a hump at 1k all point towards poor simulation.

                In any event, you have some nice drivers in hand and now measurement capabilities - time to delve into design work!
                Don't listen to me - I have not sold any $150,000 speakers.

                Comment


                • #23
                  Re: Frequency response help?

                  The speakers were inset in the entertainment center so I pulled them out as far as I could. I also pointed the mic directly at the speaker and used 1/48 smoothing.

                  Here is the results for the L and R speaker.

                  Left
                  Click image for larger version

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                  Right
                  Click image for larger version

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                  I may move one to the closet and measure it. That way I can see if it measures any different.

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                  • #24
                    Re: Frequency response help?

                    Well it flattened out considerably, but it looks like your tweeter is still too padded. Also, that sweep cuts off like a rock - this isn't an MP3 file you are using to measure, is it?
                    Don't listen to me - I have not sold any $150,000 speakers.

                    Comment


                    • #25
                      Re: Frequency response help?

                      I copied the CD to the hard drive of my PS3. Next test, I'll run it directly from the CD.

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