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’ for spike information
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
information 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 Scenario’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
precious 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 Scenario’s, you may
want to use ETC (Energy Transfer Coupler) Spikes (See
Figure 5), which are available from your local MartinLogan
dealer or on our website at www.martinlogan.com. With the
use of these spikes, the Scenario 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 5.
The ETC Spike.
Solid Footing