The M4.21 is a very high power, high SPL quad subwoofer system.

Using a hybrid horn loading technology, we have achieved significant increase in the SPL capabilities of the system with no sacrifice to the low end extension, and managed to create a system that can easily replace and outperform a stack of 4 conventional 2×21 inch reflex loaded boxes while using half the required amplifier power. This will gain significant investment savings for the customers.

The system is loaded with 4 heavy duty 21 inch 2000W AES power handling low frequency transducers with 135 mm (5.3 in) outside-inside voice coil, weather protected carbon fiber reinforced cellulose cone capable of 72mm peak to peak maximum cone excursion. The advanced technology implemented in this driver is making it a very unique and one its kind, placing it directly to the very top in today’s transducer industry.

M4.21 quad subwoofer system has a combined sensitivity of 111db 1w/1m boasting incredible 152db of peak SPL.

Having all this in place it makes the system very capable of covering the most demanding subwoofer application.