ADAM Audio A.R.T.
Accelerated Ribbon Technology

The A.R.T. tweeters and midrange units take a new approach in kinematics to move air and improve the quality of music reproduction. Based on the original works of Dr. Oskar Heil, who invented his "Air Motion Transformer" back in 1972, new electroacoustic transducers have been developed that are based on improved layouts and new materials. The membrane consists of a lamella like folded diaphragm whose single folds move according to the alternate current, thus squeezing air in and out.

All other loudspeaker drive units, whether they are voice coil driven, electrostatics, piezos or magnetostatics, act like a piston, moving air in a 1:1 ratio. This is undesirable, as the specific weight of air is much lower than that of the driving mechanics. The A.R.T. principle achieves a 4:1 velocity transformation between driving diaphragm and driven air This superior "motor" is responsible for the clarity and transient reproduction that is to be heard from the A.R.T. drive units.

The construction of the membrane in single stripes avoids the typical break up of stiff domes or cones at higher frequencies and the resultant dynamic limiting. Another factor in dynamics is diaphragm area. The cone area you can see is always the acoustically active area of the loudspeaker. By folding the A.R.T. diaphragm into the third dimension a much larger folio can be used. A factor of more than 2.5 can be seen between the sound generating area and the acoustically effective area of the diaphragm. Thus a smaller movement is needed for a given sound pressure level, enabling the unit to reach a higher sound pressure level without dynamic compression.

To improve the reproduction in the middle frequencies the A.R.T. Midrange Unit has been designed. The same principle is applied, however by using different sizes in geometry, width and depth of the folds as well as in diaphragm thickness; frequency response here starts at 300 Hz. To avoid resonance's in the most critical midband area the unit is housed in its own small cabinet that is acoustically decoupled by "floating" on a damping foam within the main cabinet. Exact transient reproduction and spatial information are the benefits of this approach. The air gap in this unit has an enormous volume compared to comparable voice coil based systems. 28 neodyme magnets of the highest strength available are used to get the efficiency needed for good overall performance. This costly decision pays off however with the unsurpassed clarity and fidelity achieved by this unit.

The principal task of an electroacoustic transducer is to generate sound from incoming alternate current. Practically all studio monitors offered today use voice coil based drive units for this purpose. To transmit the motion of the voice coil stiff domes or cones are connected to it. Air is always moved in a 1:1 ratio between diaphragm and air, and always the diaphragm area you can see is the acoustically active area. These two properties are also valid for all the other transducer principles.