More than four decades of experience and insight have been applied to the design of this truly invisible subwoofer, based on high-performance 8” woofers specially developed for the M&K Sound V Series subwoofers and ingeniously adapted to meet the extreme demands of shallow, flush-mount installation while delivering the quantity and quality of deep bass that consumers and professionals expect from M&K Sound.
The specially tuned, ultra-fast, mass-loaded dual drivers employ aluminum shorting rings for minimal voice coil distortion at long excursion. Highly rigid paper pulp cones with high inner damping ensure stability at extreme levels and low resonance.
The ultra-linear solid ferrite magnet system provides effective dissipation of heat from the voice coil to prevent power compression from limiting the acoustic output of the system.
The drivers are installed in full contact with the front baffle and the rear of the box for ideal mechanical stability to minimize driver resonances that can occur due to the limited volume of an In-Wall enclosure.
The IW28s needs the VA500 Subwoofer Amplifier. 
 
VA500 Subwoofer Amplifier
This dedicated Class D amplifer with high efficiency, cool running and low standby voltage consumption is a further development of the amplifiers built into the popular M&K Sound V Series subwoofers. The Class D switch mode power module is designed with effective power reserves to effortlessly deliver copious amounts of clean power to the IW28S In-Wall sub for extraordinary, uncompromising handling of demanding deep bass transients.
A precisely calibrated dynamic headroom control circuit constantly monitors the signal to prevent audible clipping, while maintaining the full dynamic range of modern digital audio formats.
Stereo inputs and line-level passthrough connections provide valuable flexibility for system building and future expansion. For perfect sonic integration with any satellite system, VA500 incorporates adjustable gain control including a fixed level position for reference set-up, continuously variable phase (0-180 degrees), variable crossover frequency (60Hz – 200Hz) and three-position room adaptation. The amp is one standard rack unit high and is supplied with removable handles for mounting in a 19” pro rack and feet for stand-alone placement.