The tweeter circuit is padded by a fixed voltage divider that provides a specific load to the crossover filter in front of it. The series portion of the voltage divider is bypassed with a capacitance which tends to give rising response to equalize the power response of the tweeter horn. The crossover load formed by the padding voltage divider is chosen so the circuit is slightly underdamped at the crossover point. What this does is to introduce a slight amount of peaking down low, just enough to make a flat portion in the response curve from crossover up a couple of octaves. Only after this point does the power response EQ start to take off. These are the two functions of the compensation network, and they are illustrated in detail in the crossover document on the π Speakers website.

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