Wolcott P220-M monoblocks (220w) have sounded really good on the Magnepan 3.6 speakers in Slipknot1's system. You should be able to buy a used pair at the top end of your budget. In Slipknot1's system, the Wolcotts replaced Aragon Palladiums for a significant improvement. The impressive thing for me with the Wolcotts is how resolving they are with the Magnepans at low volume levels, but have no difficulty driving the speakers to volume levels that cause me to need to leave the room. They also deliver some of the best bass response I've heard from Maggies.
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