cheapest acoustic treatment options for living room
First most people have the wrong concept about acoustics. Most people think you want a damped room with no reflections. That would be completely wrong. Reflections are good they just need to be controlled.
A good room will have sound delays of around 1 to 1.5 seconds. This creates a natural sounding room without being to over-damped, or to live.
For windows a really good option is actually vertical blinds ideally from wood, which can be angled to reflect sounds without absorbing them. Diffusion is a much better option and gives a more open and natural sound.
Some absorption can be helpful, but very careful choice in material should be used, not to absorb to much sound but to delay it. So typically very light materials where you can even see through them has a better chance of sounding good.
Another issue with absorption is that most materials are not linear in the amount of sound they absorb. They will absorb at certain frequency's and reflect at others, creating large comb-filtering issues.
Parallel walls are the issue, especially side wall reflections but again diffusion is a better option.
Now being that's your back wall that's not terrible, generally if you want anything with damping its your rear wall. Live front wall, acoustically controlled rear wall.
First most people have the wrong concept about acoustics. Most people think you want a damped room with no reflections. That would be completely wrong. Reflections are good they just need to be controlled.
A good room will have sound delays of around 1 to 1.5 seconds. This creates a natural sounding room without being to over-damped, or to live.
For windows a really good option is actually vertical blinds ideally from wood, which can be angled to reflect sounds without absorbing them. Diffusion is a much better option and gives a more open and natural sound.
Some absorption can be helpful, but very careful choice in material should be used, not to absorb to much sound but to delay it. So typically very light materials where you can even see through them has a better chance of sounding good.
Another issue with absorption is that most materials are not linear in the amount of sound they absorb. They will absorb at certain frequency's and reflect at others, creating large comb-filtering issues.
Parallel walls are the issue, especially side wall reflections but again diffusion is a better option.
Now being that's your back wall that's not terrible, generally if you want anything with damping its your rear wall. Live front wall, acoustically controlled rear wall.