Yea, I think I’m gonna try tubes on my 600 rather than getting a new HP. I kinda of don’t like saying this, but from my experience, the HD600 is extremely good and very hard to beat. I love it too much and I love my music with it, I do EQ it slightly in the sub and mid bass but other than that its perfect. I’m a complete moron with tubes and know nothing about them. Maybe something to increase the stage if possible?