The IDS-25 is very directional vertically but the column extends from floor to ceiling. It means that floor and ceiling reflections that would normally interfere with the direct radiation are effectively eliminated over most of the frequency range. At the same time, horizontal dispersion provided by the very small drivers, ensures a wide radiation angle, even at higher frequencies. This enables you to always be directly in front of the coverage area, whether you are standing or sitting. It is a significant advantage over many systems that radiate as much vertically as horizontally.
The IDS-25 has another unique feature. All frequencies are radiated as a cylindrical surface. The sound level decreases only by 3 dB for every doubling of distance. It means that you can listen closer without being overwhelmed with loud sound and makes the system ideal for use even in smaller rooms.
Normally, for a single speaker, whether it is a woofer, mid or tweeter, the sound level decreases by 6 dB for every doubling of distance. This is because each frequency is radiated as a spherical surface.
Elimination of unwanted floor and ceiling reflections, as well as less attenuation with distance, extends the useful listening area further into the room than many other systems. This is sometimes referred to as the near field, where most of the sound comes directly from the speakers and not from room reflections. When the sound is mostly from reflections, this is referred to as the far field and is room dependent. The IDS-25 can project direct sound further and extend the useful near field of your listening room from top to bottom.
In addition, low frequency room resonances are greatly reduced. This is because the lows are being radiated all along the height of each column, exciting room resonances at low amplitude. In comparison, subwoofers located on the floor can build up some resonances at very high amplitude.
