"Soundproofing" in a "real studio" requires things like cutting the concrete slab, and laying 10 layers of drywall over the studs for mass. And while you are at, tearing the walls and ceiling down and rebuilding so none of the walls are parallel, including the ceiling to the floor, and that room-symmetry is maintained. Or simply bulldozing your house down and starting over. Not suggesting that.
Roxul absorbs sound. That is what those numbers mean below the frequency. A "1.0" means most of the incident energy that struck the batten did not bounce back into the room. A "0.5" means about half the energy was absorbed. Bottom Line --> Roxul has excellent acoustical performance. If you download REW5.0, you can load up the REW Frequency Generator and excite the room with low frequency tones (40 Hz seems to work good). Then walk around your room and listen. You will be amazed. You can use this method to find the spots where the bass frequencies are piling up in your control room. Double or triple layers of Roxul (6 inch or 9 inch thick) make good (and cheap) bass traps. Build frames and cover with cloth from the fabric store and put them where the bass piled up.
You can also use Roxul to control early reflections. It works WAY BETTER than that "acoustic" foam triangley-looking stuff you so often see people using (looks cool, costs a lot of money, and works like crap - and why they rarely publish their ASTM C 423 Absorption COEFFICIENTS). Mount panels on wall behind monitors, and to right and left, and on ceiling above listening position. Places where early reflections are going to interfere with critical listening.
And, no, I don't work for Roxul.