Room Acoustics; Your Room; Terminology; Solid Footing - MartinLogan Dynamo 800X User Manual

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oom CoustiCs

Your Room

This is an area that requires both a little background to understand
and some time and experimentation to attain the best performance
from your system. Your room is actually a component and an impor-
tant part of your system. This component is a large variable and can
dramatically add to or subtract from a great sonic experience.
All sound is composed of waves. Each frequency has its own
wave size, with the lower, or bass frequencies literally encompass-
ing from 10 feet to as much as 40 feet. Your room participates in
this wave experience like a swimming pool with waves reflecting
and becoming enhanced depending on the size and shape of the
room and the types of surfaces in the room.
Remember that your audio system can actually generate all of the
information required to recreate a sonic event in time, space, and
tonal balance. Acoustically, the role of an ideal room would be to
neither delete nor contribute to that information. However, nearly
every room does to some degree.

Terminology

Standing Waves
Sound coming from a speaker bounces around in a room until a
pattern emerges—this is called a standing wave. Typically, this is
only a problem with frequencies below 100Hz. When this hap-
pens different parts of your room experience either an excess or
a lack of bass.
Some people believe that having a room without parallel walls
will eliminate this effect. The truth is that non-parallel walls only
generate different standing wave patterns than those that occur in
rectangular rooms.
Usually, you can excite most of the standing waves in a room by
putting the subwoofer in a corner. Listening position determines
which standing waves you will experience. For instance, if you sit
in a corner you will hear most of the standing waves. This can be
an overpowering experience. Sitting next to a wall can also inten-
sify the levels of the standing waves that are experienced.
Resonant Surfaces and Objects
All of the surfaces and objects in your room are subject to the
frequencies generated by your system. Much like an instrument,
they will vibrate and "carry on" in syncopation with the music, and
may contribute in a negative way to the sound. Ringing, boomi-
ness, and even brightness can occur simply because surfaces and
objects are "singing along" with your speakers.
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Resonant Cavities
Small alcoves or closet type areas in your room can be chambers
that create their own "standing waves" and can drum their own
"one note" sounds.

Solid Footing

After living and experimenting with your subwoofer, you may want
to use ETC™ (Energy Transfer Coupler) spikes. With the use of
these spikes, the subwoofer will become more firmly planted on the
floor and, consequently, bass will tighten. It is best not to implement
the spikes, however, until you are secure in the positioning, as the
spikes can damage the floor if the subwoofer is moved.
Spike Installation Instructions:
1 Carefully lay the subwoofer on its side to gain access to the
bottom of the feet.
2 Remove the rubber cap from the foot to reveal the spike.
Caution: Make sure your hands and any cabling are clear of the
spikes. Do not slide the subwoofer as spikes are sharp and can
damage your floor or carpet.
Figure 27. To access the spikes, remove the rubber cap..