as much clean power as you can afford for the mids, and 50-75rms for the tweets. i was bi-amping mine with a GT22 on the mids and a GT20 on the tweets, and it sounded great, but needed a bit more for what i was looking for. a GT22 bridged to each woofer, with the GT20 powering the tweets did the trick //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif