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Thread: What exactly is the "correction amp" for??

  1. #41
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    Make sure the max/min is +-5v centered at 0.

  2. #42
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    Okay, I set it so it idles at 0V, and maxes at 5. It still goes distorted tho. What happens, is at a low speed, like 10K it appears fine. As I try to bring it up to 20K, stuff shrinks and grows, goes inside out etc. Its really weird o_O

  3. #43
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    What's the scan angle? Set it to 8 degrees and check what you can do with the ILDA test pattern. Try tuning a little and see if that helps.

  4. #44
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    OK I even tried tuning. I got the test pattern to what I thought was good, went over to laseroids and i still has the same distortion problem. Didn't someone say these cards have some sort of inbuilt limiting??

  5. #45
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    OK, I realise pictures/video will help you guys greatly. I'll run into work soon and grab my good camera, and see if I can get a good pic/vid of what its doing.

  6. #46
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    Quote Originally Posted by Things View Post
    OK I even tried tuning. I got the test pattern to what I thought was good, went over to laseroids and i still has the same distortion problem. Didn't someone say these cards have some sort of inbuilt limiting??
    Supposedly, but if I use the default settings it works fine.

  7. #47
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    You only really run into the AGC (inbuilt limiting) when using WMP to play back wavs, since it boosts the gain greater than 1 on the front channels.

  8. #48
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    So does any one have any idea what could be causing it to distort at higher speeds? I doubt its my scan angle, my amp outputs 4.73V max on both channels, so I wouldnt be pushing it. THe only thing I can think of, is either my computer is too slow to send all the data, or there is a cap or something on the sound card thats distorting it, or there is another EQ or something somewhere on windblows.

  9. #49
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    If you can play drlava's full swing positive wave and measure a DC voltage on the output of every channel, then there is no cap.

    James.

  10. #50
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    James, just to confirm, the GROUND of the sound card, is the - side, of that capacitor near the USB plug? Would that capacitor possibly be screwin with it? I dunno why else it would just randomly distort at higher speeds.

    Also, since these are dual opamps, how do you use them in the dual configuration?? I only have 2 TL072's ATM, but I saw on your DAC correction amp, there is only 3, but you have 6 channels?

    Thanks

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