Both models feature ATC's renowned drive units, hand built in its UK facility. Of particular note is the new SH-25-76S 25mm/one-inch soft dome tweeter, the first to be designed and built by ATC, and the result of six years of research and development by Managing Director Billy Woodman and R&D Engineer Richard Newman. "The tweeter is designed and built with the same no-compromise philosophy as all other ATC drive units," notes Newman, before continuing: "The design takes notes from the highly-regarded ATC midrange dome by utilising a dual-suspension design, negating the requirement for Ferro-fluid, and avoiding the detrimental effects of this drying out over time, a feature considered to be of utmost importance for longterm consistency." The massive neodymium motor with heat-treated top plate is optimised to ensure an extended frequency response (-6dB @ 26kHz) and low non-linear distortion. The geometry of the waveguide is designed for optimum dispersion and made from a precision-machined alloy so that the entire structure is extremely rigid and free from resonances.
The bass/mid driver used in both loudspeakers is ATC's proprietary 150mm/six-inch Super Linear device. Constructed with a 75mm/three-inch voice coil and a short-coil, long-gap topology, it combines the high-power handling and low-power compression usually only found in large, high-efficiency systems with the fine resolution and balance of modern high-fidelity systems. Unique to the drive unit is ATC's Super Linear technology, which, by employing specialist materials in the magnetic circuit, reduces third harmonic distortion in the lower midrange.
The electronics in the active design have also had considerable development time invested in them, resulting in reduced noise and distortion (a further -10dB @ 10kHz) and a reduced operating temperature for improved reliability. The amplifier design is a revised version of ATC's discrete MOSFET Class A/B design with 200W and 50W continuous power available for the bass and high frequency sections, respectively. The user controls have also been improved over the previous generation with more flexible input sensitivity controls and a revised low frequency shelf control to help achieve good balance in difficult acoustic conditions. The amplifier includes protection circuits for both DC offset and thermal overload.
The cabinet has been restyled to more closely follow the larger monitors in ATC's professional range and is constructed from heavily-braced MDF. Highly damped, elastometric panels are bonded and stapled to the cabinet's inner walls to suppress cabinet panel resonances, while the enclosure's front panel is heavily radiused to reduce cabinet diffraction, improving the frequency response and imaging. The loudspeaker can be wall mounted via a K&M 24120 Wall Mount (available separately). Note that the cabinet requires modification to accept the 'top-hat' mount.
Ideally suited to critical nearfield listening applications in all control rooms, LCR surround monitoring in small-to-medium control rooms, and surround channels in medium-to-large control rooms, anyone looking to seriously improve their reference nearfield monitoring experience surely owe it to themselves and their studio setup to take a listen to the SCM20ASL Pro (V2) and/or the SCM20PSL Pro in action. EQ, balance, and edit faster, with more consistent results and reduced listening fatigue using the latest reference nearfields from ATC.