MartinLogan Source Speakers Placement & Room Acoustics, Listening Position, The Side Walls

Models: Source Speakers

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PLACEMENT & ROOM ACOUSTICS

PLACEMENT & ROOM ACOUSTICS

Listening Position

Your speakers should be placed approximately two to three feet from the front wall, the wall in front of the lis- tening position, and about two feet from the side walls. Your sitting distance should be further than the distance between the speakers themselves. You are trying to attain the impression of good center imaging and stage width.

There is no exact distance between speakers and listener, but there is a relationship. In long rooms, naturally, that relationship changes. The distance between the speakers will be far less than the distance from you to the speaker system. However, in a wide room, you will still find that if the distance from the listener to the speakers becomes smaller than the distance between the speakers themselves, the image will no longer focus in the center.

Now that you have positioned your speaker system, spend time listening. Wait to make any major changes in your initial setup for the next few days as the speaker system itself will change subtly in its sound. Over the first 72 hours of play the actual tonal quality will change slightly with deeper bass and more spacious highs resulting. After a few days of listening you can begin to make refinements and hear the differences.

The Wall Behind the Listener

Near-field reflections can also occur from your back wall (the wall behind the listening position). If your listening position is close to the back wall, these reflections can cause prob- lems and confuse imaging quality. It is better for the wall behind you to be absorptive than to be reflective. If you have a hard back wall and your listening position is close to it, experiment with devices that will absorb information (i.e. wall hangings and possibly even sound absorbing panels).

The Wall Behind the Speakers

The front surface, the wall behind the speakers, should not be extremely hard or soft. A pane of glass will cause reflections, brightness and confused imaging. Curtains, drapery and objects such as bookshelves can be placed along the wall to diffuse an overly reflective surface. A standard sheet rock or textured wall is generally an ade- quate surface if the rest of the room is not too bright and hard. Walls can also be too soft. If the entire front wall consists of heavy drapery, your system can sound dull. You may hear muted music with little ambience. Harder surfaces will actually help in this case.

The front surface ideally should be one long wall without any doors or openings. If you have openings, the reflection and bass characteristics from each channel can be different.

The Side Walls

A good rule of thumb is to have the side walls as far away from the speaker sides as possible. However, MartinLogan’s unique controlled dispersion electrostatic transducer inher- ently minimizes side wall reflections—a position as little as two feet from the side walls often proves adequate. Sometimes, if the system is bright or the imaging is not to your liking, and the side walls are very near, try putting curtains or softening material directly to the edge of each speaker. An ideal side wall, however, is no side wall at all.

Experimentation

Toe-in

Now you can begin to experiment. First begin by toeing your speakers in towards the listening area and then fac- ing them straight into the room. You will notice the tonal balance and imaging changing. You will notice that as the speakers are toed-out, the system becomes slightly bright- er than when toed-in. This design gives you the flexibility to compensate for a soft or bright room.

Generally it is found that the ideal listening position is with the speakers slightly toed-in so that you are listening to the inner third of the curved transducer section. A simple, yet effective method to achieve proper toe involves sitting at the listening position, holding a flashlight under your chin and pointing it at each speaker. The reflection of the flashlight should be within the inner third of the panel (see figure 2).

Figure 2. Flashlight toe-in technique.

8Placement & Room Acoustics

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MartinLogan Source Speakers Placement & Room Acoustics, Listening Position, The Wall Behind the Listener, The Side Walls