Check out the Odyssey Stratos amplifier, stereo or dual mono configurations. Stereo units are often available used for $600-$800. Dual Mono are less frequently available. Many units are available used with the cap upgrade (Extreme version), or you can send them back to the factory after purchase and have them upgraded. All models have plenty of current, and the Extreme versions have, well, an Extreme amount of dampening power for all those hungry Mani woofers. Since these are sold factory direct, they are a good bargain new, and a silly deal used.
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http://www.odysseyaudio.com/index.html