A Passive House has a thick thermally broken building envelope. Avoiding thermal bridges in construction not only reduces energy consumption but also makes for a quieter home.
High quality, well sealed, triple pane window units also keep it quiet inside. The whole approach to air-sealing helps keep the noise out.
A radically reduced energy demand allows for smaller mechanical systems. Smaller mechanical systems are often quieter. As well a higher quality unit can often be purchased for less than a similar larger unit.