SCM45A Pro



The SCM45A is a completely new design but shares many features with the highly-successful SCM25A. It fills a gap in ATC’s product range for a mid-size three-way that can be used in near- or mid-field positions, has high output and extended low frequency for its size but without compromising the overall balance for which ATC is so well known.

Like the SCM25A, the new SCM45A is an active three-way with an unprecedented linear response across the critical mid-range, as well as across the rest of the audible range. In contrast to the SCM25A, the SCM45A has a second woofer for deeper bass response and increased SPL capability, as well as ATC’s new proprietary dual-suspension tweeter for increased resolution in the top-end. In addition, the SCM45A is physically symmetrical (not mirror imaged) and sized for placement on a meter bridge. The SCM45A is thus ideal as a center speaker between a pair of SCM45A’s or ATC SCM50ASL’s.

The ATC SCM45A uses ATC’s new one-inch dual-suspension “Super” tweeter, the first to be designed and built by the company and the result of six years of research and design by Billy Woodman (managing director) and Richard Newman (R&D engineer). The mid-range driver is ATC’s hand-built three-inch soft dome and two 6.5-inch bass drivers deliver the lower frequencies. All of the drive units are powered by ATC’s proprietary active amp pack, a three-channel discrete MOSFET class A/B design with 150/60/25 for the bass/mid/HF respectively.


Key features:

  • Proprietary ATC 25mm/1″ Dual Suspension Super Tweeter
  • ATC hand built 3″/75mm Soft Dome mid-range driver.
  • 2 x ATC hand built 6.5″/164mm carbon-paper cone bass drivers.
  • On-board grounded source 235 watt Class A/B Tri-amplifier.
  • Compact size with high output and low cut-off frequency.
  • 6 year warranty.


Tech note on remote amplifier options (PDF)

Dual Amp Pack Remote Mounting (PDF)

Triple Amp Pack Remote Mounting (PDF)


“I’m reacting to the mix and making choices much more quickly. Any problems are instantly apparent – it’s like, ‘oh, that’s out of phase’ or ‘that needs to come down 1.5dB.’ Plus, it’s more exciting. Once I have things is a good place, it’s fun to turn it up because the ATC’s sound so great! The imaging is wide and precise. And of course, as advertised, the ATCs translate perfectly. Every mix sounds just right on my home stereo, in my car, on my phone, and anywhere.” – Mat Mitchell (Producer/Engineer/Songwriter)


Maximum Continuous SPL: 112dB (per pair at 1m)
LF Driver: SB50-164SC 6.5"/164mm Short-coil carbon-paper cone
MF Driver: SM75-150 3"/75mm Soft dome
HF Driver: SH25-76S 1"/25mm Soft dome
Amplitude Linearity: 70Hz - 17kHz (+/-2dB)
Cut-off Frequencies: 42Hz - 25kHz (-6dB freestanding)
Horizontal Dispersion: +/-80° coherent
Vertical Dispersion: +/-10° coherent
Input Connector: Rear panel mounted female XLR (pin 2 +)
Input Sensitivity: 1V rms (ref. full output)
Input Sensitivity Trim 0dB to -6dB (continuously variable)
Input Impedance: balanced >10k?
Amplifier Output Power
LF: 150W rms
MF: 60W rms
HF: 25W rms
Crossover Frequencies: 380Hz & 3.5kHz
Crossover Filters: 4th order critically damped with phase compensation
Low Frequency Boost: 0dB to +3dB at 40Hz (continuously variable)
Overload Protection: active FET momentary gain reduction
Mains Power Requirements: 115/230V, 50/60Hz via rear panel switch. 100v 50/60Hz factory set
Mains Power Consumption: 56VA (standby max), 154VA (typical 1/8th power), 375VA (max)
Thermal Output: 53W (idle), 130W (1/8th power)
Speaker Weight: 79.2lbs per cabinet
Speaker Dimensions: 13.9"H x 23.62"W x 14.8"D
Shipping Weight: 92.4lbs / 42kg
Shipping Dimensions: 21"H x 31"W x 23"D