The ADM 30 is an extremely compact power packet, that despite its very modest dimensions, produces a very noticeable sound pressure. Quote: “the pulse response is phenomenally good indeed; for example a bass drum sounds almost like it’s live… the acoustic pattern fans out perfectly, similarly the lower frequencies… (Martin Hömberg, Audio Professional). Equipped with a DMC ™ controlled, 8 inch speaker with a carbon fibre membrane and a special cone which was specifically designed for this speaker, the ADM30 is faithful to KS Digital’s philosophy of high impulse fidelity with the lowest possible level of distortion. At the crossover frequency, the directivity of the sound from the cone of the tweeter has been optimally matched to that of the 8” driver. An optional D/A converter enables the direct connection to a digital workstation or a mixer console.

Linear Phase Reproduction using DMC ™ Membrane Control
By virtue of their physical characteristics, all loudspeaker drivers produce errors when reproducing music signals. These errors may include decaying oscillations or delayed build up etc. These can affect, amongst others, the characteristics of amplitude, phase or frequency which is why one tries to minimize their affects with active filtering. Additional filters in the signal path however, distort the phase characteristic of the speaker and therefore reduce the impulse fidelity of the reproduction. The solution comes from a completely different approach to the problem of correcting the frequency characteristic: DMC ™ Membrane Control. This system controls the movement of the membrane so that it exactly follows the music signal.

Technically speaking, a loudspeaker driver is a special linear motor. As with every linear motor, speed, acceleration and distance travelled can be measured. As the speed and direction of movement of the membrane changes to the rhythm of the music, its exact position is being recorded by a sensor in the controlled driver. The values are fed into the analogue controller where they are compared to the simultaneously measured values of the music signal. Only any differences to the expected values are transmitted to the output stage for correction. In this way it can be continuously guaranteed that the membrane only moves exactly in the way that is necessary to reproduce the signal input. In this way, decaying oscillations and other errors can be ruled out. With sound travelling at 330 meters/sec and the corrective electronics working at almost the speed of light, the errors are corrected even during their formation with zero latency. This basic principle however, means the very finest of attention to detail in its implementation and the design of sensors and active components and naturally requires the knowledge of the theoretical context, experience and feel. This effort is rewarded with a neutral, pure musical reproduction, a linear amplitude and (!) phase frequency characteristics down to the very lowest of frequencies without (!) latency times.