Technologies
MPD (Micro Pleated Diaphragm) High Frequency Transducer
AMT design was first invented by Dr Oskar Heil in the 1970s. However, all designs typically suffer from a null in the
frequency response around 40kHz. Using FEA modelling techniques, Monitor Audio engineers were able to find the
root cause of this null and develop a solution. This phenomenon was eliminated, allowing the driver to operate with
uniform output to over 100 kHz. We call this unique innovation Micro Pleated Diaphragm (MPD).
The folded MPD diaphragm exhibits a surface area typically eight times that of a
conventional dome tweeter, and around thirteen times that of a pure ribbon tweeter.
This large surface area improves the conducted heat path and the open front
increases the convection. The power handling is also improved by the high sensitivity
of the tweeter. The AMT design also provides a constant non-reactive load to the
amplifier, this means it’s able to deliver power more efficiently with lower distortion.
The MPD is designed to bend and does not rely on its structural integrity to extend high in the
frequency range. There are no break up modes throughout the entire frequency range, exhibiting clean sonic character,
free from any harmonic artefacts.
C-CAM® (Ceramic Coated Aluminium/Magnesium)
C-CAM is an innovative alloy material originally developed by the aerospace industry. It exhibits ideal qualities for use
as loudspeaker cones, being extremely rigid, yet light enough to yield high overall efficiency. C-CAM is formed from
an alloy of aluminium and magnesium, which undergoes stress-relieving processes in manufacturing to avoid surface
deformation and molecular weakness. A layer of pure ceramic (alumina) is depleted onto the surfaces to produce a
completely rigid exterior. C-CAM cones are designed to have high resistance to bending stress. When formed into a cone,
C-CAM material provides increased clarity and reduced distortion compared to conventional cone materials.
RDT®II (Rigid Diaphragm Technology 2nd Generation)
RDT II is a composite ‘sandwich’ structure made from ultra-thin low-mass
skins, bonded to a honeycomb NomexR core material. The overall thickness of
the RDT II diaphragm is only 2mm, yet it exhibits 150 times the strength of a
conventional loudspeaker cone. RDT II is a unique, innovative development
conceived by Monitor Audio engineers for the new Platinum II series. It uses two
skin materials with dissimilar mechanical properties. C-CAM is used for the front
skin, while the rear skin is made from a woven carbon fibre. This combination is able
to reduce distortion by over 8dB above 300Hz, which equates to a 60% reduction in the
energy of harmonic components, making RDT II the lowest distortion cone technology in Monitor Audio’s history.
ARC® (Anti-Resonance Composite)
A cast thermo-set polymer loaded with minerals to provide very inert, optimally damped components. This material is
ideal for high-end acoustic applications where a high degree of structural rigidity and vibration damping is required.
ARC is used for mid-range housings and baffle components. ARC is a unique material, developed specifically by
Monitor Audio engineers for the Platinum II series. Its properties ensure energy is damped out and not emitted as
high-Q resonance.
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