Thanks Bill I'll look into those. It still seems to me that I can't use the amp's filters because of the way the X is setup. There are both tweeters and woofers in the front and rear channels. This prevents configuring an amp to favor one or the other. Instead, I need to send the full range to each channel and then let the speaker's crossover handle it. This analysis is based on using a single 4 channel amp.

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