The cardioid principle is all about cancelling out frequencies radiated to the rear. While medium and high frequencies can be radiated in directional patterns, low frequencies are spherical. This often leads to an unpleasant excess of low bass on and behind the stage. Organisers are also increasingly setting precise demands for sound distribution, for example in marquees and urban stages.
The SONAR 115 SUB D meets all the requirements, both mechanically and acoustically, to implement effective cardioid setups quickly and easily, reducing the low bass radiated to the rear by up to 30 dB! This not only makes performing on stage much more relaxed, it also results in a better sound, as microphones no longer pick up unwanted low frequencies.
A second SONAR 115 Sub D can be used to increase the sound pressure level in the bass range. The classic full-stack setup (shown on the left) with two subs projecting forward boosts the sound pressure by level 3 dB in all directions. But what makes the SONAR 115 Sub D so special are its cardioid capabilities. It has two special presets that allow you to configure a cardioid setup (shown on the right), where the lower sub projects to the rear, without the need for any complex calculations or time correction.
To do this, simply direct the lower SONAR sub to the rear and select the Cardioid Rear preset, and direct the upper sub to the front, selecting the Cardioid Front preset. Now both subs can play perfectly together without having to make any further adjustments.