Basement Acoustic Treatment
I've recently been able to set up a new 2 channel system in the basement of a 100+ year old home. The basement itself was renovated and finished about 6 years ago. At this point, I'm at my wits end when it comes to acoustically treating this space. All measurements are rough but I have included pictures to help explain. I have a pair of Heil ESS AMT1a's being pushed by a McIntosh MC2105 2-channel amp. One important thing I should mention is that these speakers have a driver on the front AND the back. I plan on adding a subwoofer in the near future (separately amped) and my main sources for music are vinyl and streaming. For streaming I use a Chromcast Audio running to preamp through an optical cable. I also use this setup with a projector for TV and PS4 but I am not overly concerned with having the best sound quality for viewing, more concerned for good listening sessions. I am running all video sources through an HDMI switcher with a built-in DAC going to the preamp through RCA's.
--First off, the front and back walls are recessed roughly 16.5" at 3' from the floor, and then recessed again 7.5" one foot higher up the wall, creating two "shelves." It is hard to explain and I may not have done a good job of it, but the pictures should show what I mean.
--The front wall is 21'4.5" long, the speakers are 5'6" from the side walls and 1' away from the front wall. I have a little bit of room to move them around if necessary. I originally had them toed in a bit, but got a better sound and bigger soundstage after facing them straight forward. The projector screen is not acoustically transparent but can be rolled up. There is a 2'X3' window behind the projector screen.
--There is another recess to the left of the front wall, 18" deep and 3'11" long at 3' from the floor. Directly to the left of that is a countertop with sink that is 6' long and 2'9" deep. To the left of that, a small hallway leading to the bathroom and laundry room doors. To the left of the hallway is another protruding wall that houses part of the hvac unit. It is 3'9.5" long and 3'6.5" deep.
--The back wall is 24'3" has an 8'8" long section protruding out one foot from the wall where it was framed out to cover an old, no longer functioning fireplace. If facing the back wall, the protrusion starts two feet from the left. There is also a 2'X3" window to the left of the protrusion
--The wall to the right of the listening position is basically flat except for drywall framed out to cover a support beam. The framing and drywall is 10" long and protrudes out 1'10.5".
My main objective here is to not get extremely scientific and technical, I'm just looking to deal with the echo and make my system sound as best as possible. The bed and bookshelf will be removed and there will be a pool table placed in the space behind the couch. My plan is to add shelving for books and records in the recess to the left of the front wall, but this would just be a preference it would not be for any acoustic treatment effect. I am open to doing something else to that space if it helps with the sound. I am also open to moving around the rugs (there are two in the room) and placing absorption and diffusion panels wherever they should go. Acoustic treatment is already somewhat over my head and on top of that the room is laid out so strange.
Also, I would like to hang the mirrors that are leaning against the back wall, but I realize more glass in the room would be detrimental so those aren't necessarily a must. There is no need to worry about sound leakage from the room, but I would like whatever treatment needed to at least be somewhat aesthetically pleasing.
Any advice and input is much appreciated, HELP HELP HELP!