ATC Drive Units 03 - No Shadow

Soft Dome Mid-Range

There are few engineering developments in any field that have effected change to the extent that ATC’s Soft Dome Midrange has on the monitoring of sound and particularly of music and voice. First produced in 1976 ATC’s soft dome represents the very best of midrange loudspeaker design and performance combining a smooth response from 350Hz to 3.5KHz, exceptionally low colouration, high power handling capacity, low power compression and high output level.

This performance is achieved in ATC’s soft dome drive unit by having a very linear low distortion drive system comprising a 75mm diameter short coil operating in a long magnet gap supported on 2 suspensions to guarantee controlled coil movement, maintain concentricity with the very tight gap-coil clearances and also ensure excellent heat dissipation and power handling. The magnet gap is also in a magnetic circuit that is saturated and therefore not affected by the non-linearity due to hysteresis of the steel used in the magnetic assembly. The dome diaphragm, driven at its edge by the coil-former assembly, is a soft woven fabric impregnated with a viscous damping medium to attenuate unwanted resonances and ensure a smooth response with very low audible colouration. The response of the soft dome diaphragm is further improved by mounting it in a phase correction flange the profile of which is a mirror image of the dome. All of these elements combine to produce a midrange driver of exceptional fidelity and neutrality.

ATC’s soft dome midrange is a common element in all ATC three way systems ensuring consistency between models and the best performance money can buy.

Loudspeaker Technology Ltd, Gypsy Lane, Aston Down, Stroud, Gloucestershire, GL6 8HR.
Tel: +44 (0)1285 760561 Fax: +44 (0)1285760683 Email:

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