Studio Room treatment help, please

So, I recently had the chance to finally set up a small recording studio in the basement. Unfortunately, there is no room treatment at this time and the sound just bounces and rumbles all of the place down there-- The room is going to be used as dual room for both mixing and tracking. But, most likely will only be tracking drums and bass at the same, so hopefully only some baffling will be needed. Room dimensions are: 40'x15'x7.5' ceiling But, I really need some room treatment to tighten up the room. My budget at this point is limited, So, I probably going to start building a few Bass Traps and hang them in the corners and possibly build a 4" thick cloud over the drum-set and maybe even the mixing console. However, my two concerns are: First the uneven Left corner wall that is in-front of the mixing console. You can see by the photos that the LEFT corner is about 5" lower than the right. So, what is the best way to handle that??? should I build the build the bass trap from floor to ceiling-- all the way up to the top of each Tri-corner (even though they wont be symmetrical) or, . .Do I try and make both Left and Right corners even-- By building both bass traps to 6 feet high, than adding (2) 24"x24"x4 square panels in the Tri-corners and then lower the Right side square panel to meet the same angle as the Left (that would even the symmetry) But is that necessary?? Secondly-- is that if you look at the photos of the back of the studio-- to the left of the couch- where the shelves are-- is that little angled alcove that creates THREE corners. Do I need to hang Bass Traps in all THREE of those corners of the alcove or can I just hang one bass trap in the corners of each side of the back wall. Anyway, sorry for rambling, . . any advice you guys can give me, would be really appreciated. Have a great weekend fellas! :(

you could put up absorbers across each corner in the room. you can also add them on the wall-ceiling corners behind the drum and bass, and each side of the mixer. you could construct a drum riser with 1" 703 under 29/32 and 3/4 ply to get the drum off the floor (and not create a membrane abosrber which kills off the kick...) on a more elaborate basis, you could put up some 2x4 frames and put up slats and larger absorbers... realistically though, if you were going to do that, with that much space I'd divy up the room with a drum and vox booth and some gobos for amps...