I heard headphones are a good ide for those of us with hearing issues. What sort of headphone do we need? Special plug? Wireless?
This recent thread will give you some idea.
https://community.ricksteves.com/travel-forum/tech-tips/headphones-c453fac0-bc1b-479d-969f-712aa1c9b00e
The buses generally have PA systems, so you will not need headphones on the bus. The "whisper" listening devices are mostly used on walking tours.