ATC SCM12 Pro passive studio monitor
The ATC SCM12 Pro compact passive monitor brings world-class ATC monitoring to home and project studios. The most affordable monitor in the ATC line, the SCM12 is the result of several innovative ATC driver technologies. The SCM12 Pro features ATC’s Constrained Layer Damping (CLD), which brings significant performance improvements to bass/mid drivers, by reducing harmonic distortion in the critical midrange, improving frequency response, as well as dispersion. The SCM12 Pro also incorporates ATC’s SH25-76 tweeter, which employs a unique dual-suspension system that eliminates the need for ferro-fluid, which can cause a decline in high-frequency performance as it thickens. These and other proprietary technologies are responsible for the highly accurate sound and long-term reliability of ATC monitors.
ATC SCM12 Pro passive studio monitor in one take:
- Compact high performance 2-way studio monitor
- For critical nearfield listening in control rooms of all sizes; LCR surround monitoring in small-to-medium control rooms
- Proprietary ATC 6″/150mm CLD mid/bass driver
- Proprietary ATC 1″/25mm dual-suspension tweeter
- Six-year warranty
ATC makes what many consider to be the world’s finest studio monitors, as evidenced by a client list that reads a who’s who of artists, engineers, recording studios, film, post, and broadcast facilities, as well as pro audio manufacturers and educational institutions. Obviously, it takes an attention to fine detail and proprietary technology. Let’s take a closer look at ATC technology.
Linear off-axis response:
To achieve superior loudspeaker performance, there must be a balance between all measured characteristics, including magnitude response, phase response, power response, time domain response, distortion characteristics, and power handling.
Starting with the off-axis response of the loudspeaker, ATC engineers ensure that the phase relationship of the drivers maintain a linear response.
Proprietary soft dome tweeter
In order to maintain the highest levels of performance, ATC controls all aspects of the loudspeaker system to ensure the lowest levels of linear and non-linear distortion. Along with manufacturing their own bass, bass/mid, and midrange drivers, ATC couldn’t rely on OEM or stock designs, and spent considerable time creating a soft dome tweeter to meet their high standards.
Nearly all 25mm tweeters use a voice coil suspended in the magnetic gap of the motor immersed in ferro-fluid. The fluid adds mechanical damping, transferring heat to the metalwork and suppressing rocking modes. Over time the fluid starts to thicken presenting resistance to the moving coil assembly, causing the magnitude response to decline.
ATC endeavored to design a tweeter free from the limitation of ferro-fluid while simultaneously overcoming the engineering problems that arise without its use. As with all ATC drivers, the tweeter was approached with optimum performance in mind.
Borrowing the dual suspension technology from their midrange soft dome, which forces the use of a larger voice coil, ATC used extremely large, high-grade neodymium magnets in the motor assemblies to get the required efficiency and top-end extension. ATC also heat-treats the top plate (magnetic annealing) to squeeze that bit extra performance out of the components. Large, well-designed motors mean lots of flux in the gap, which in turn results in extremely low odd-harmonic distortion, an extended magnitude response, and an excellent time-domain characteristic.
Bass/Mid driver construction
ATC drivers feature massive magnet motor assemblies, with no-compromise optimization for each voice coil diameter. Hand-wound voice coils use only high-density, edge-wound, flat OFHC (oxygen-free high thermal conductivity) ribbon copper wire and operate in precision magnetic gaps. Front and rear venting not only reduces airflow noise, but also increases power handling capacity, and therefore, long-term reliability.
The perceived sound quality of a loudspeaker is dependent on its power response, particularly when listening to high-energy transients. As such, high-performance loudspeakers should exhibit a broad and even dispersion with frequency—a factor that ATC takes great care to achieve.
ATC’s largest bass/mid driver is 6.5″ with a crossover of around 2.5kHz, which ATC engineers consider to be a practical limit in a 2-way. In a 2-way system capable of high dynamic range, an ideal crossover point has to be compromised a little to minimize HF driver distortion and increase reliability. If the bass/mid driver was significantly larger, it would become more directional, causing the horizontal response around crossover to suffer. As driver diameter increases to achieve greater bass extension and higher SPL, maintaining good off-axis response would require the move to a three-way system.
Short throat waveguide
ATC tweeters have a carefully designed short-throat waveguide. Deeper throats would affect the balance of the device, both on- and off-frequency, and if taken to the extreme would further increase distortion. At the chosen crossover frequency, ATC’s 25mm tweeter effectively radiates omni-directionally as desired.
ATC believes that the key to superior performance is designing drivers and systems for use at high levels, and not rigidly adhering to known reference levels for testing. The parameters of drivers vary with level. As such, ATC designs for those changes. Performance at 1W or 90dB SPL is relatively easy, but what happens at 100W or 110dB SPL? ATC knows and designs for it.
Who Using ATC?
ATC users range from artists such as Sting, Pink Floyd, The Rolling Stones, Eric Johnson, Enya, Kate Bush, film composer, James Newton Howard, and many more. ATC users include producer-engineers known for their discriminating ears, such as Bruce Swedien, Hugh Padgham, Chuck Ainley, Ed Cherney, producer-engineer-equipment designer, George Massenburg, mastering engineer Bob Ludwig, and John McBride of Blackbird Studios. ATC monitors are also in use at recording studios, sound stages and broadcast facilities, such as East West Studios, Air London, Sony Music Studios, Paramount Studios, Warner Brothers, and BBC UK, to name a few. Even pro audio equipment manufacturers who depend on critical listening for product design depend on ATC, including Shure Microphones and Dolby Laboratories.
The SCM12 Pro brings ATC’s world-class monitoring to home and project studios. For more information, call or chat online with your Westlake Pro sales consultant.
ATC SCM12 Pro specifications:
- Drivers: HF ATC 1″/25mm dual suspension Soft Dome (SH25-76 6 Ohm)
- LF ATC 6″/150mm Constrained Layer Damping (CLD) (SB50-150CLD 8 Ohm)
- Amplitude Linearity: 80Hz – 16kHz (+/-2dB)
- Cutoff frequencies: 56Hz – 22kHz (-6dB freestanding)
- Dispersion: ±80° Coherent Horizontal, ±10° Coherent Vertical
- Maximum Continuous SPL: 108dB (per pair @ 1m)
- Crossover frequency: 2.2kHz
- Recommended Power Amplifier: 75 to 300 watts
- Nominal Impedance: 8 ohm
- Connectors: Binding Posts/4mm Plugs, bi-wire
- Cabinet Dimensions (H x W x D): 15-11/16″ x 9-13/32″ x 9-5/16″ (400 x 238 x235mm)
- Weight: 24 lb./11kg (per cabinet)