Looking for a freq response tool...

Discussion in 'Home Theater Projects' started by Dave Poehlman, Oct 4, 2004.

  1. Dave Poehlman

    Dave Poehlman Producer

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    Is there a website that will allow you to input measured frequencies and draw a logarithmic graph for you?

    I've found an excel spreadsheet that'll draw a graph for you but not with the traditional logarithmic frequency axis (For some reason, excel will only allow you to draw the vertical axis logarithmically)

    Maybe one of you "java-heads" could whip up something like that. Oh, and while you're at it, throw in an option to adjust for the Radio Shack SPL meter calibration.... and maybe toss in a wavelength calculator on the side... that way I wont have to look up the formula all the time. [​IMG]
     
  2. JamesFarina

    JamesFarina Agent

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    Hi Dave,

    After you plot your points in Excel just right click on the horizontal (frequency axis), click the SCALE tab and click on the box for logarithmic scale.

    Hope this helps,

    Jim F.
     
  3. Dave Poehlman

    Dave Poehlman Producer

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    Thanks James, I found it... apparently you can only do it on a scatter plot scale.

    Anyway.. FWIW, I made an Excel sheet that has all of the Stryke BassZone test CD frequencies listed and will adjust for the Radio Shack analog meter and draw a nice logarithmic graph.

    You can download the spreadsheet HERE.

    Just plug in your raw readings into the white column and the adjusted graph appears on the right. Then you can just copy the graph and paste it into your favorite graphic software and put it on your website or show it off to your friends.. whatever.

    Not to take full credit, but, I modified the spreadsheet from BFD, and expanded the frequencies to the full spectrum.

    P.S. You can also either enter the actual dB rating or the difference off of your reference level (ie: -5dB, 10dB, etc..) the chart adjusts to fit.
     

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