I know I am like the only person around here who cares about this, but the mention of the imax adding cost because of noise is true or any soundproof home theater. The biggest thing I learned in my own build was just how critical the sound isolation of everything is. You can build a sound proof theater and it will be ok. The expense is really high for the noise floor you get. Once you recognize all the sources of noise intrusion it gets nuts.
The noise isolation in my theater is pretty insane and I didn’t achieve a noise floor as low as some (or I would have liked) due to cost constraints. For example:
- I isolated the ducts in my theater but it’s not on its own unit.
- I didn’t dig up and report a decoupled cement floor, adding decoupled decking instead.
- I didn’t use spring isolators for all the channel clips, just rubber.
- I didn’t fully decouple the hvac because lifting it into spring isolators meant redoing the main trunks. I also didn’t use decoupled on the main trunks.
- I didnt pour a decoupled subfloor above the theater
- I didn’t change out all the ducts with lines ducts and only liked the ducts around the theater
- I used rubber isolators for the dishwasher, it’s not fully decoupled
- I didn’t wrap all the plumbing around the theater in lagging
All of this would have added tens of thousands of dollars in materials and labor, but is what is necessary to really create a room with the kind of noise floor that these guys look for.
Soundproofing correctly is REALLY expensive and requires a lot of engineering. I studied the topic at a graduate level for years and none of that prepared me for actually doing it for the first time.