Mine isn't peaky. I have no tolerance for peaky, and even if I did, my wife would let me know. In fact, I've always been able to gauge whether the treble is dialed in by how my family behaves when the music is playing. If the treble has glare or is edgy, they get loud and irritable. When it's right, they calm down. I read a review in Sensible Sound that observed that the plastic-bodied AT440MLa had an upper midrange peak, but not the AT150MLX, which the reviewer felt was very neutral and linear, but had plenty of dynamics, trackability, and separation.
07-20-08: Gadfly
Johnnyb53, I heard those AT carts are peaky, bright. You should check out the Ortofon 2M's. I have the 2M Black and I love it.
Actually, in spite of its trackability, linearity, and higher level of detail over my DL-160, I'd describe the sound of my AT150MLX as lush. Lush in the sense that the details enrich the musical picture rather than distract the listener from the music. My current setup conveys a connection to the music as I've never had before in my home system.