At 4Khz, we'd have 8 ohms reactive impedance, and the tweeter would be at -3dB
at 2Khz, we'd have 16 ohms reactive impedance, and the tweeter would be at -7dB
at 1Khz, we'd have 32 ohms reactive impedance, and could expect the tweeter to be -13dB, and
at 500Hz, we'd have 64 ohms reactive impedance, and would expect -19dB from the tweeter.

But what if the tweeter's impedance at resonance is 40 ohms at 600Hz? The reactive impedance of our 5uF
crossover capacitor is only 42 ohms at this point - so the tweeter will be only -3dB attenuated at its resonant
frequency. That's a long way from our expected -18dB, and we'll probably destroy this tweeter.............

Could you use a notch filter or zobel in the circuit to remedy this 40 ohm peak? (with cross-over remaining the same)