efficiency quotes anquotes 696x374For good cancellation behind inline cardioid subwoofer arrays like end-fire and gradient, it's mission critical that the subwoofers have matched levels. But how does the physical displacement between the subwoofers affect the array's performance over distance?

Prof. John VanderkooyProf. John VanderkooyIn 2010 Prof. John Vanderkooy presented an AES paper offering analytical proof and compelling evidence that the acoustic center for low frequencies resides in front of the loudspeaker at a distance of approximately two-thirds of the baffle radius.

Pick your battles"If a battle can't be won, don't fight it"

- Sun Tzu -

Whenever we experience too much of a particular frequency or frequency range, we're tempted to resort to equalization to resolve the situation. In this article I will demonstrate that the effectiveness of EQ relies entirely on the relative level separation from other sources.

Mind the gap - Part IIIn part II of this series of articles I will elaborate on my preliminary findings about the possibly beneficial effect of introducing gaps between adjacent enclosures in cardioid stacks and arrays.

Mind the gapA short time ago I was very fortunate to have gained access to a former air force base featuring ample real estate with a solid underground.

An ideal environment for subwoofer measurements where I got to measure all typical inverted stack cardioid setups.

And while I’m still in the middle of processing all data, I would already like to share one preliminary but potentially interesting observation.