There are several powered monitors in the Emotiva Pro line that fit your budget and use a Heil AMT-type folded ribbon tweeter. I haven't heard these Emotiva monitors yet, but I've heard several speakers that use some variation of this tweeter by GoldenEar and MartinLogan. The treble on these is airy and extended, yet smooth and totally devoid of the resonances, ringing, and overshoot so common to certain pistonic dome tweeters.
