
I'm building a studio in the loft of my barn. We designed the structure to follow the gambrel style roof, and it's completely free standing. I sheeted the outside of the structure with OSB and 5/8 drywall, then filled the 2x6 walls with tons of insulation. Parts have more like a foot of insulation, due to the cavities provided by the gambrels. On the inside I've started with another round of 5/8 drywall, and its starting to get nice and quiet inside, apart from doors and such.
So far, I'm fairly confident in my sound proofing. The real question I have though, is how to go about finishing the surface of this room for good acoustics? Initially I was thinking of drywalling the surface, for a nice clean painted finish that I could then start treating, however when we had just a bit of drywall on the walls, I already started noticing quite an echo in certain places of the room. I think that's because of some of the angles.
Overall room size btw is approx 20 wide x 25 long, give or take a few inches, and height in the center of the ceiling is close to 11'.
After hearing the sound of the drywall, I thought maybe I'd save some money I was planning on using for drywall, and re-use a bunch of donnacona I have - I think that's also called soundboard, it's that fibrous paper-y sort of stuff. I got a load of it out of a friend's studio for free. Problem is, it's ugly as sin, and I hate the thought of covering the ceiling with it in any way that can be seen. So, I thought of covering it with some kind of cloth, and then perhaps strapping some wood over top, following the joists, to bring back the gambrel style architecture into the room, but also to provide some sound deflection and breakup.
I was sort of thinking of doing from the shoulder up in with that stuff, and the lower part of the wall in drywall.
However, then I read that you don't want too dead of a room either, and now my head is just spinning

All that, to say this - what are your thoughts on finishing roughly half the surface area of the room (excluding floor) with donnacona? Any thoughts or experience on covering that stuff to make it more pretty? Can it be painted, and if so, how much does that affect its acoustic qualities? Has anyone dealt with angles of this nature before?
I attached a pic to give a rough idea of the angles involved.
Any thoughts / suggestions / comments would be more than appreciated - I have tons to learn about this stuff, and little time to do it!

Best regards,
Jonathan