How to reduce echo in a restaurant

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

1. 1
   Researching acoustic panels
2. 2
   Considering hiring an acoustician
3. 3
   Adding large area rugs and soft furniture
4. 4
   Hanging floor-to-ceiling curtains
5. 5
   Putting foam behind canvas wall photos
6. 6
   Installing wood slat sound panels
7. 7
   Using bookshelves and plants to break up flat walls

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.