MartinLogan CLS IIz user manual Dispersion Interactions, Controlled Horizontal Dispersion

DISPERSION INTERACTIONS

Controlled Horizontal Dispersion

Your CLS IIz’s launch a 30-degree dispersion pattern when viewed from above. This horizontal dispersion field gives a choice of good seats for the performance while minimizing interactions with side walls (See Figure 2). Make sure both speakers stand exactly at the same vertical angle, otherwise the image can be skewed or poorly defined. The wave launch of both speakers is extremely accurate in both the time and spectral domain. Consequently, small refined adjustments can result in noticeable sonic improvements.

Controlled Vertical Dispersion

As you can see from the illustrations, your CLS IIz speakers project a controlled dispersion pattern. Each CLS IIz is a 4- foot line source beginning a few inches above the floor level (See Figure 3). This vertical dispersion profile mini- mizes interactions with the floor and the ceiling.

Figure 2. MartinLogan CLS IIz’s deliver a 30-degree wave launch dispersion pattern distributed horizontally.

Three Major Types of Dispersion

In the field of loudspeaker design, it is a known fact that as the sound wave becomes progressively smaller than the transducer producing it, the dispersion of that wave becomes more and more narrow, or directional. This fact occurs as long as the transducer is a flat surface. Large flat- panel speakers exhibit venetian blind effects due to this phenomenon. This is why most manufacturers opt for small drivers (i.e., tweeters and midrange) to approximate what is known as a point source wave launch.

Historically, most attempts to achieve smooth dispersion from large flat-panel transducers resulted in trade-offs. After exhaustive testing of these different solution attempts, we found an elegantly simple, yet very difficult to execute solution. By curving the radiating surface, we create the effect of a horizontal arc. This allows the engineers at MartinLogan to control the high frequency dispersion pattern of our transducers. That is why you see the gentle curve on our products.

Figure 3. Your CLS IIz speaker system is a 48 inch line source viewed vertically.

10 Dispersion Interactions