Urei Little Dipper and notch filters


2005-07-11 5:40 pm
I'm looking for a little dipper or high quality shelving/notch filter to attenuate room resonances. Does anyone have a ciruit diagram for a Urei 565 "Little dipper" or similar high quality notch filter. I could possibly trade diagrams of from an Amek BCII if these are of use. Many thanks.
Here is a schematic for a parametric EQ which can give you -15dB notches with 12dB/octave (2 pole) slopes. The bandwidth control can be adjusted from a wide 3.3 octaves to a very narrow .05 octave. Only one filter (band) is shown, but you can make as many as needed. The supply should be a clean, regulated bipolar 15 volts. If you need help with the supply, I can find you a drawing.


  • parametric eq.gif
    parametric eq.gif
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