headphone amp


Looking for suggestions for a headphone amp that will drive either grado or sennheiser phones (low to high z). Something that retails for under a 1 k $. Have considered the Creek amps and the Grado amp - any experience with these (and what phones wre used with the amps), or other recomendations for amps in the 1 k $ retail and below would be appreciated?
musicnoise
I have no experience with Creek or Grado, but I would recommend in the strongest possible terms to look also at the Yamamoto HA-02. Granted, it will fill out your $1k budget completely, but if it cost twice that much it would still be an excellent buy imo. It sports two small Western Electric WE 408A tubes and is designed for low impedance headphones if I understand the website correctly (Yamamoto-san's explanations are, erm, somewhat idiosyncratic, but then again, my Japanese ain't that brilliant either, so what am I complaining). I am using the amp with Audio Technica ATH W1000 Sovereign headphones (40 ohm). Should you be interested, there is a review by Srajan Ebaen on 6moons with a lot of technical information.