adding insulation

i have a garage that i'm in the process of converting to a studio. it is 23" wide 17" deep. ceiling slopes from 11.5" to 7.5" (across the 17" deep). at the moment all the walls are open. old 2x4 framing everywhere ...even the ceiling. most is 24" on center, some newer stuff is 16" on center. the short story is i've already spent 17k with residing, foundation, door, etc. . just going from shack to room. the initial idea was a room in a room design, but that will have to wait. i have to say i like the way it sounds. sure, there is bleed both in and out, but i have work arounds for the time being. something about all the old wood sounds good to me. there are 2 issues i do hear. 1, there is a ping. not sure if this is from stuff (there is a lot in the room) or the actual space. 2, i can hear some muddy modal action where the ceiling is lower. the best sounding place is about 5 feet out from the corners with high ceilings. i'm also beginning to realize is may be very hot/cold due to lack of insulation. quesion: i was thinking about insulating the ceiling and possibly the front face wall (hit by the sun) 23"x11.5". my thinking is the ceiling (shortest dimension) would be more problematic for modes. front face is the second shortest dimension. this way i'd have some reflective wood (long dimensions) and some dead walls (short) now it seems r-14 for 2x4s isn' going to cut it acoustically. i'd need compressed fiberglass, rockwool, etc. ideas? suggestions? thanks.

Read this site. That is the best suggestion I can think of. What you are asking is not a question, it is looking for approval. "23"x11.5". my thinking is the ceiling (shortest dimension) would be more problematic for modes. " My thinking is that these dimensions, divisable one by the other, BOTH will be problematic. But problems are to be expected.