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Perhaps the ceiling/roof weighs more and is harder than before, which might tighten up the sound. Soft wood walls make the sound warmer and looser."
Agree - I have these in many of my rooms as well - https://www.tmsoundproofing.com/Electric-Box-Seal.html?sku=BOXSEAL_STC012102
Agree - I have these in many of my rooms as well - https://www.tmsoundproofing.com/Electric-Box-Seal.html?sku=BOXSEAL_STC012102