[Louis Boyd]

RichD wrote:
This may be a dumb question, I never studied acoustics....

If you look into the wrong end of a telescope,
everything looks reduced, 'anti-magnified'.
Is there anything analogous acoustically?

In both cases, the phenomena is described
by wave equations -

--
Rich


It should be simple to demonstrate a Galilean telescope (one positive
and one negative lens) which will magnify or minify an acoustic image
using an ultrasonic imaging device and some common optical lenses.
They would only need to be made of a material with a different velocity
of propagation of sound than a liquid they are submerged in. The
velocity of propagation of sound is somewhat analogous to the velocity
of propagation of electromagnetic energy to demonstrate refraction at
material boundaries.

"Magnify" doesn't have the same meaning in imaging and non-imaging
situations.

An acoustic "telescope" doesn't have to be refractive. A two mirror
Cassegrain reflecting telescope can focus sound as well as
electromagnetic energy. I've experienced that working on microwave
antennas.