What's Acoustics anyway?
Why do people buy acoustic products? There has
to be a reason for investing in sound control
products, and that is simply the need to get
the best out of the sound systems in our rooms.
But the main question we should be asking is
why does sound need to be controlled
anyway? This question will take us over the
next few minutes into a journey of sound characteristics
and its behaviour, especially those occurring
inside an enclosed room, whether it is a recording
or mastering studio, a home cinema or even an
Although people may not be conscious of the
science behind sound, the truth is that most
of us have already been in places where we said
or thought: "Such an awful sound in this
place", and we're not talking about music
we're talking about going into
a room and just knowing that there was something
wrong with the sound of it, whether it was long
echoes or simply confusing sound. This happens
because sound is just like a light from a lamp
in a room with a window. The path the light
takes is not just the straight line between
the lamp and the surface that's in front of
it (whether it is the floor or a wall). Instead,
light covers the whole free space of the room
and even goes into other rooms through the window.
So it is with sound. Whatever may be its source,
sound will fill the whole room in all directions
and even fly into other rooms through the floor,
ceiling or walls, since sound waves can travel
by any solid, liquid or gas material.
Acoustics is simply the way sound is affected
by the physical properties of the space where
it is being produced, and this is why clients
want good acoustics and why acoustic products
companies develop materials that will change
the physical properties of the space; so that
in the end, we all come up with rooms with adequate
amount and distribution of sound, ensuring clarity
of speech and "completeness" of music.
So when considering the properties of a room,
what we are really trying to avoid are acoustic
defects such as reflections, flutter echoes,
reverberation and standing waves.
We'll show you how each one of these things
occurs in your own room, preventing you from
benefiting from the full potential of your sound
system. Fortunately there are solutions and
we're also going to show them to you!
Reflections are the acoustic phenomenon that
happens in any kind of room, regardless of its
shape, function or size: sound always changes
when it encounters a plain surface.
As we've previously mentioned, sound doesn't
move only in a straight line from its source
into the listener's ears. Sound
waves coming from a certain point spread out
in many directions, and when they encounter
an obstacle, like a wall for example, they react
by producing "counter-waves" as if
they were being produced by another source different
then the real one.
Therefore the result is quite
simple to imagine. Instead of having a clear
sound, the listener will feel a lot of confusion
coming not only from the audio system, but also
from the whole room itself.
One of the main problems that
reflections can bring is echo, which happens
when reflected sound clearly distinguishes itself
from the direct sound.
In order to find a solution, science
started from a simple question: If the
problem occurs right after sound waves get into
touch with plain surfaces, and if thats
not a possible variable to change, what can
be done to catch those sound waves
and stop or diminish them?
The answer would rapidly put foam
and similar materials into a major position
in the world of acoustic solutions, namely those
related to absorption. Acoustic absorption products
made from foam perform like energy converters,
catching reflections (sound energy) from a sound
source and by a resistive process turning them
into heat energy, diminishing their strength
and allowing the sound in a space to become
clearer, as we can see in the images below.