"From thousands of acoustical measurements I have done with MAD Arrays, I have a very strong understanding how MAD speakers work. MAD Planar Magnetic Surface Arrays configured with proper EQ has almost linear phase within the working frequency range. If you plot phase vs. frequency on a linear frequency range scale you will see a flat line, which tells you that there are absolutely no issues with phase. Sound is very coherent.

The MAD Array is built with 6x9 full-range planar magnetic transducers. Due to diaphragm size, these transducers are very directional and above 4-5KHz dispersion pattern starts to narrow down. For example, at 10KHz horizontal dispersion angle is only 15° (+/- 7.5) while vertical is only 10° (+/-5°). If you go higher and higher in frequency, transducers have narrower dispersion angles. In the A9 Array horizontal splay angle is ~11.25° and that was the worst compromise we decided to tolerate between overall dispersion and sound quality. At frequencies above 8 KHz dispersion patterns don't overlap completely and you can hear small variations in SPL (notches) if you listen between drivers. This is especially noticeable in near field, within a couple of meters from the array. Notches are frequency dependant and they become deeper at higher frequencies. So, we are not talking here about “phasing” but rather of directional properties of individual drivers.

If you move far away, this problem is minimized and barely noticeable. This phenomenon happens well above voice range and with the program material it is quite acceptable.

Most of the classical Line Array systems have off axis problems in the middle of the vocal range (1-3KHz), which is in the order of magnitude worse than what we have.

By using bigger drivers we have created a very simple, full-range system that is very reliable and, in normal use, almost indestructible. Power handling of the array, if properly sized, exceeds many times the power of the amplifiers and everything is running safe and nice. Distortion levels always remain very low within the operation power range of the amps. This is totally opposite from other speaker systems."

D.Colich, CTO HPV Technologies LLC