Just got my Alpha Dog today. It's a secondhand pair owned by the reviewer at Headfonics.com. Out of a lot of the high-end headphones I've tried these are the least flawed for my tastes. The HE-560 wowed with it's wide open sound, clarity, and smoothness. It wronged in soundstage depth and had a midrange that felt a little hollow. The LCD-2 had beautiful, deep, high textured bass and a nice, full, and warm midrange. It has great depth and a nice center image. It lacked openness, air, and soundstage width though. The HD700 was awesome too. Dark, forward, clear, and smooth with a soundstage for me beat those mentioned earlier. Too bad it had that terrible treble peak. Some tracks were plain unbearable.
My first impressions of the Alpha Dog are that not of awe but of growing appreciation. Coming from the Fidelio L2, the treble was surely less forward and I actually the L2 to etched with more developed treble but neither being harsh unless the recording would be bright. Soundstage is the best I've heard for a closed back (I haven't tried THAT many). I hear it to be wider than the LCD-2 around the width of the L2 or slightly wider. The depth was equal to that of the LCD and better than the other headphones mentioned save for the HD700. My gripe would be bass which was a little lacking for my tastes as I recall the HE-560 to be even punchier on certain tracks. I've remedied this with a half turn on the bass screw. I'd turn it another half turn but I think it might steal the show of the true star.
From the start, the Alpha Dog has mids that easily impress and lure. Not as warm and full bodied as that of the LCD-2 but with added clarity and retained smoothness, the midrange of the Alpha Dog plays well across all tracks I've heard them with. I'd say the midrange on my rig is slightly warm as if only to smoothen it, intimate, but still mostly neutral. Vocals are lovely and music like Hip-Hop have easily intelligible speech. The last aspect I love about the Alpha Dog is the speed. The Alpha is quite laid-back yet decay is never the least bit slow never allowing notes to blur into each other.