Yep but you don't even need the epiphany set to do so. Many builds prove that. 70% attack speed on gear from crystal affix, epic affix, nature. Not sets though since they are conditional or skills .
You can even go over cap of the default 60% cap and still activate the bonus as long as 70% attack speed is on gearhow I did so, 45% attack speed crystal affix, 1-2× epic affix of 15% attack speed. Or 1 epic attack speed and 4 nature's of attack speed or so.