True, a plate amp would do the trick, but only for the intitial prototype. I'm trying to keep the component costs as low as possible. Also, for the second iteration I will need to use servo drive of some sort for near-DC and impulse signals.The plate amps have to sum the signals and cross them over at some point. A plate amp has a seperate amp for the sub, but can still accept amplified full range signals. The plate amp will need to filter, sum, and amplify. I was simply trying to find a way to remove the amplify piece.