The Resistor and Capacitor Values
    The table below gives all values for the 1st, 2nd, 3rd with one section, 3rd with two sections, and 4th order filters. The base frequency is 1000 Hz. To decrease the frequency, scale either the resistor or the capacitor values down by 1000/F, where F equals the desired crossover frequency.
    To increase the frequency, scale either the resistor or the capacitor values up by F/1000, where F equals the desired crossover frequency.

                              NOTE
   Do not scale both resistor and capacitor values at the same time (or the frequency will not change).       

      "Hey, these values don't match the ones in my textbook!" It turns out that there are two different ways to determine where the crossover frequency falls; the -3 dB frequency, or the degree of phase shift frequency.  We chose the former; many books choose the latter.  Our choice makes more sense for loudspeaker crossovers; their choice, for single filters.           

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