ATC C4 Sub Mk2

The combination of newly designed 12-inch unit, optimized motor structure and 300W Class AB amplifier provides audiophiles and movie lovers with excellent performance and high-level subwoofers.

Known worldwide for its signature high-output, low-distortion audio engineering and trusted by musicians, studios, live sound engineers and audiophiles for over 50 years, The Acoustic Transducer Company (ATC) is proud to Announced production of C4 Sub Mk 2 active subwoofer system. Designed to combine the highest standards of driver and electronic engineering in one system, the C4 Sub Mk 2 incorporates a new proprietary ATC 12-inch SS75-314SC bass driver powered by a newly developed 300W Class AB amplifier design. These components Entirely handmade and installed at ATC’s production headquarters in Stroud

New ATC bass driver
The C4 Sub Mk 2 features the new SS75-314SC bass driver, the first driver specifically built for ATC bass systems and developed by the R&D team to reproduce the lowest four octaves of the subwoofer. audio tape. To achieve this, the design utilizes ATC's signature long gap/short coil configuration pushed to its natural limits, with an extra-long 30mm magnetic gap surrounded by a 6-inch/150mm N48M neodymium magnet, which is ATC's first completely redesigned motor system, featuring a new rubber roller surround for high deflection capabilities, a new star wheel for optimized compliance geometry, and high-flow motor ventilation for low noise and compression.

The new 300W Class AB design is precisely optimized for the requirements of the new driver, resulting in fast, dynamic bass with minimal coloration. Two balanced line inputs provide connections for a stereo or AV/home theater system, while two balanced outputs can be used to feed cooperating "main" stereo speakers or "daisy chain" multiple subwoofers. The low-pass filter is an analog fourth-order Linkwitz-Riley with filter frequency options to ensure optimal integration with partner speakers. In addition, an industry-standard 80Hz low-pass filter and "off" option (for external processing) feature a polarity switch, variable 180° phase adjustment, and step attenuators over 21 dB range for precise level matching.

C4 Sub Mk 2 speakers
Handcrafted and finished in the ATC speaker factory, the C4 Sub Mk 2's 70-litre loudspeakers share styling with the brand's 'Classic' and 'Tower' range of loudspeakers, featuring 25mm/1in thick panels and heavy-duty bracing. It's available in standard Cherry, Black Ash, Walnut and Oak solid wood veneers, in Satin Black and Satin White finishes, or in Premium Rosewood, European Crown Cut Walnut, Burr Magnolia and Leather. Solid oak veneer, with optional high-gloss finish and black/white piano paint (optional for extra money)

ACOUSTIC SPECIFICATIONS

Drive Unit – Bass: 1 x SS75-314SC 8Ω

Low Frequency Cut-of f: 22Hz (-6dB, half space, low pass filter set at 80Hz).

Low Pass Filters: 50Hz, 65Hz, 80Hz, 320Hz. (-6dB, 4th order Linkwitz Riley).

MaxSPL: 110dB continuous, 116dB peak (IEC Weighted Pink Noise, 1m, half space, low pass filter @ 80Hz).

Sensitivity: +4dBu ref. 88dBC (single channel driven, Gain +6dB, Level 0dB, pink noise, low pass filter @ 80Hz).

ELECTRONIC SPECIFICATIONS

Amplifier type: Grounded Source MOSFET based Class AB, convection cooled.

Output Power: 300W in to 8Ω.

THD+N: <0.003%/-90dB, at 100Hz, 300W into 8Ω over 90kHz bandwidth.

Balanced Inputs: 2 x Rear Panel Mounted Female XLR, pin 2 hot.

Input CMRR: 90dB at 200Hz.

Input Impedance: 20kΩ (differential).

Balanced Outputs: 2 x Rear Panel Mounted Male XLR, pin 2 hot.

Output Impedance: 100Ω (differential).

Frequency Response: <2Hz (-3dB) – 320Hz (-6dB, set by panel-controlled LP filter).

Low Pass Filters: 4th Order Linkwitz Riley

Gain Control: 0, +6dB, +10dB.

Level Control: 0dB -11dB in 1dB steps. Total range 21dB with use of Gain switch.

Phase Control: 0 -180° ref. Input .

Polarity Control: In-phase/Out-of-phase ref. Input .

Limiter: ATC Active FET Momentary Gain Reduction.

Sensitivity: 1.55Vrms for full power (single channel driven, Gain 0dB, Level 0dB)

Mains Input: 220-230V or 115V – Factory set. Please observe panel markings and labels!

Power Consumption: Idle 8W/14VA. 1/8th Power 170W/230VA. Full Power 500W/600VA.

Additional: Mute via ¼”/ 6 .35mm Jack socket, controlled via latching footswitch*.
* Footswitch supplied separately, latching type, ¼”/6.35mm jack connection.

PHYSICAL SPECIFICATIONS

Net Weight: 42kg / 92.6lbs
Dimensions: HxWxD 568x464x500mm 22 ¹⁵ ⁄ ₁₆ ” x 18 1/4” x 19 ¹¹ ⁄ ₁₆ ”