MartinLogan CLS IIz - Manual (Page 9)

Room Acoustics 9
on the floor or solid surface, it can shake as it produces
sound and, consequently, the sound can be compromised.
If your speaker is sitting on the carpet and only foot gliders
are used, the bass can be ill defined and even boomy. The
use of spikes is recommended to insure secured footing for
your speakers. (See Solid Footing, this page, for spike infor-
mation and installation instructions).
Dipolar Speakers and Your Room
MartinLogan electrostatic loudspeakers are known as dipolar
radiators. This means that they produce sound from both
their fronts and their backs. Consequently, musical infor-
mation is reflected by the wall behind them and may arrive
either in or out of step with the information produced by
the front of the speaker.
The low frequencies can either be enhanced or nulled by
the position from the front wall. Your CLS IIz’s have been
designed to be placed two to three feet from the front wall
(the wall in front of the listening position) to obtain the
best results; however, your room may see things differently.
So listening to the difference of the bass response as a
result of the changes in distance from the front wall can
allow you to get the best combination of depth of bass
and tonal balance.
Now that you know about reflective surfaces and resonant
objects, you can see how the midrange and high frequencies
can be affected. The timing of the initial wave as it radiates
to your ears, and then the reflected information as it arrives
at your ears later in time, can result in confusion of the pre-
cious timing information that carries the clues to imaging.
Consequently the result is blurred imaging and excessive
brightness. Soft walls, curtains, wall hangings, or sound
dampeners (your dealer can give you good information
here) can be effective if these negative conditions occur.
After living and experimenting with your CLS IIz’s, you may
want to use ETC (Energy Transfer Coupler) Spikes (See
Figure 1), which are available from your local MartinLogan
dealer or on our website at www.martinlogan.com. With
the use of these spikes, the CLS IIz will become more firmly
planted on the floor and, consequently, bass will tighten and
imaging will become more coherent and detailed. 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 speaker is moved. MartinLogan ETC spikes will fit
any common 1 /
4
inch thread insert that may be found on
your other audio equipment (racks, speakers, etc.).
Spike Installation Instructions:
1. Carefully lay your speaker on its side to gain access to
the bottom.
2. Remove existing feet or spikes. Thread new spikes into
holes and screw them in all of the way.
3. Tighten jam nut snugly by hand. Do not over tighten
the nut.
4. Right the speaker.
Caution: Make sure your hands and any cabling are clear
of the spikes. Do not slide speaker as spikes are sharp and
can damage your floor or carpet.
5. Adjust to level by rotating spikes. Tighten the jam nut
securely when satisfied that speaker is level.
Caution: Walking the speaker may result in a broken spike.
Figure 1. The ETC Spike.
Solid Footing