Humidity has two victims in an AV room, speaker drivers and projector optics, and prevention for both is cheap. The rule for anything unused is simple: power it on for an hour monthly through the wet season. Electronics prefer being used to being stored.
Speakers first. Sustained humidity can soften paper cones and corrode terminals and crossover contacts, and coastal cities see this most: a monsoon in Mumbai or Kochi does more to a speaker than three years in Delhi. Keep speakers off directly damp walls; an external wall that sweats in July transfers that moisture into the cabinet behind it. Leave breathing space around them rather than pushing them into a wet corner. If a room stays shut through the monsoon, air it or run the AC occasionally so the moisture does not settle. One habit I would build: look behind the grilles seasonally. Grille fabric hides moisture damage on a cone or surround until it is advanced, and by the time it is visible through the cloth the driver is often past saving.
Projectors are the more expensive worry. Lens fungus is the classic monsoon casualty, and it favours an unused projector in a humid room. Fungus grows on the coatings inside the lens assembly and it does not clean off; once it has etched the glass, the lens is the repair. Prevention is almost free. Run the projector regularly, because its own heat dries the optics from the inside. If it must be boxed for months, put silica gel in the box and change it. Never box a warm unit airtight; you seal the moisture in with the lens and give the fungus a head start.
Where does the rule stop mattering? An air-conditioned room that is used daily manages its own humidity, and equipment in it needs nothing extra. The rooms that need care are the shut second-home theatre, the guest room projector, and anything near an external wall in a coastal city.
If you already suspect a soft cone or a fogged lens, send us a photo before running it hard. Some of this is recoverable if caught early, and none of it is if caught late.
Not sure what fits your room and budget? Share your room size and budget on WhatsApp. It is a two-minute answer with a floor plan.
