I use two Rel Stentors and the addition of the second sub made some suprising diffrences. It didnt just help the bass it actually opened the soundstage and increased stereo seperation. It cleaned the sound up and articulated fine detail through the whole frequency range.
That said I would buy the best Rel you can afford. You can always upgrade down the road and get a second one.
That said I would buy the best Rel you can afford. You can always upgrade down the road and get a second one.