Can you focus sound ?

Sound can be focused like light, but in the case of sound the “optics”
must be much larger because you are dealing with longer wavelengths.
The effect is heard in some domed buildings such as the Capitol in
Washington, and St Paul’s Cathedral in London providing noise
background conditions permit.

Large parabolic reflectors can be used very effectively to send and
receive sound over significant distances. Check out your local science
museum or exploratorium – there may be a demonstration. It is also
possible to refract sound and focus it using a lens. The lens is
constructed from a large thin bubble, say 2 metres across, filled with
carbon dioxide. The effect is not very pronounced.

Sound can be directed by making use of constructive and destructive
interference. This idea is used in column speakers, and commercial
systems for reducing noise levels outside the dance floor area of
discos.