Sound Fields

The actual measured sound fields of our commercial Audio Spotlight models are below. All measurements were done in an anechoic (reflection-free) room, with laboratory-grade microphones at 1kHz.  

These sound fields show the remarkable isolation ability of the Audio Spotlight technology. Even one step outside the beam, sound levels are reduced by over 90%

Comparison to other "directional" sound sources

A few traditional loudspeaker makers have promoted so-called "directional" sound sources, to mimic the unique technology and appeal of the Audio Spotlight. But the physics cannot support the claims - all other sound sources are forever limited to the "wavelength versus size" physics constraint. Making a bigger loudspeaker does increase its directivity, but only slightly. How close can regular speakers get to the Audio Spotlight?

For formal theory, with mathematical proof, please read the whitepaper "Fundamental Limits of Loudspeaker Directivity". Below are actual, physical measurements of Audio Spotlight systems, and similarly-sized "directional" traditional loudspeakers.

1D SPEAKER ARRAY (SOUND BAR)

This speaker array is marketed as being "highly focused" while providing "isolated listening", though actual field specifications are conspicuously omitted from their datasheets. A line array like this is expected to be slightly directive in the long axis, but completely omnidirectional about the short axis. Here's how it measures, compared to an Audio Spotlight speaker of similar size:

 

1D Sound Bar

1D Sound Bar (vertical)

AS-24i

 

2D SPEAKER ARRAY (SOUND PLANE)

Speaker panels, whether they are made from a single radiating element, an array of small loudspeakers, or the opening of a dome, are acoustically equivalent, and are simply the 2D form of the Speaker Bar mentioned above. All have the same maximum directivity. In this case, the horizontal and vertical dimensions are equal. Therefore, the sound field pattern is identical to that of the Sound Bar’s largest dimension, but for both horizontal and vertical angles. 

This one is also marketed as being "highly directional". Here's how it compares to the Audio Spotlight technology:

 
 

2D Array

AS-24i

 

Clearly, no loudspeaker technology can remotely approach the directivity and isolation abilities of the Audio Spotlight.