You may need less power handling from your high frequency driver than you might expect! High frequency drivers will only see a small percentage of system power, if a proper crossover network is used. The woofer section sees the brunt of the power in a system, because lower frequencies are more abusive. A lower crossover point is more abusive on the high frequency driver. As a general rule of thumb, we estimate that the high frequency driver will see about 20% of the system power with a 1.5kHz-2.5kHz crossover, 15% with a 3.5kHz-5kHz crossover, and 10% with a 5kHz and up crossover (all based on a minimum 12dB/octave slope). So, for a 400 watt system with a 1.6khz crossover, you may only need an 80 watt high frequency driver. Plus, high frequency drivers are typically much more efficient than woofers. You must attenuate the high frequency driver to more closely match the output of the woofer. For every 3dB of output that is attenuated, the power is cut in half. If you attenuate the 80 watt high frequency driver 6dB in the example above, you would only need a 20 watt high frequency driver for the 400 watt system.