ATC C4 Sub Mk 2 Subwoofer Landing in Australia

ATC draws on its considerable professional and high-end audio engineering expertise to produce the new C4 Sub Mk 2 active subwoofer system, and it’s slated for arrival in early March 2024.

The new subwoofer employs the new SS75-314SC 300 mm (12 inches) custom woofer driver which has been designed by ATC specifically for the C4 Sub Mk 2. The new low-distortion/high excursion driver has been developed in-house by ATC engineers with a long 30 mm magnetic gap and a short coil topology. This magnet motor architecture maintains the voice coil within the magnet structure and is said to provide improved voice coil cooling (also helped by a flared vent which runs through the centre of the motor) while minimising power compression. The arrangement also provides improved driver reliability and longevity.


The magnetic gap is “surrounded” by a powerful 150 mm (6 inches) neodymium magnet system. ATC states the magnet motor is a first for the company while being the most powerful it has ever produced. Also new to the driver construction are the remodelled rubber roll surround and new spider design.

The C4 Sub Mk 2 houses a new 300 watts Class-A/B amplifier. A signpost to ATC’s professional audio designs, the subwoofer’s rear panel offers twin XLR inputs and outputs (no RCA connectivity provided) and 6.5 mm jack ‘Foot Switch’ input and output. Crossover frequency can be switched between 50 Hz, 65 Hz and 80 Hz and there’s an ‘Off’ setting for full-range/natural roll-off configuration. There’s a ‘Gain’ toggle switch (0, +6 and +10), a ‘Level’ rotary switch (from -11dB, to 0dB) and a continuous rotary switch for ‘Phase’ between 0 and 180 degrees.

The C4 Sub Mk 2’s 70 litre cabinet inherits the styling of ATC’s ‘Classic’ and ‘Tower’ loudspeakers. The enclosure in constructed from 25 mm (1 inch) panels and features heavy bracing. In order to cater and blend into all domestic environments, ATC offers a wide range of cabinet finishes in natural wood veneers, gloss lacquered wood veneers, and gloss Black and White.


ATC recommends the C4 Sub Mk 2 as the perfect mate to its SCM19, SCM20, SCM40, SCM50 and SCM100 active/passive systems.

ATC told SoundStage! Australia the subwoofer has been “Designed and engineered with a focus on resolution and integration, the C4 Sub Mk2 delivers a more balanced and coherent experience for the listener, extending the low-frequency response without masking details or changing the tonal character in the upper bass/lower mid-range.”


The new ATC C4 Sub Mk 2 active subwoofer will be available in Australia in limited number from March 2024 via importer Pure Music Group’s network of country-wide retailers.

ATC C4 Sub Mk 2 Active Subwoofer
Price: From AU$8750

Australian Distributor: Pure Music Group
+61 409 504 805