Overview

Compact 3-Way Active Loudspeaker

The SCM25A Pro Mk2 is a compact 3-way high-performance active studio monitor loudspeaker, based around a 6.5/164mm bass driver loaded in a 25-litre vented cabinet. The monitor’s combination of exceptional mid-range clarity, high-output, extended bass response and modest size make it ideal for nearfield monitoring across a wide range of critical applications.

The 3-way monitor features proprietary drive units designed and manufactured by ATC. Low frequencies below 380Hz are handled by a 6.5/164mm bass driver, mid-range frequencies between 380Hz & 3.5kHz by the ATC 3”/75mm soft dome mid-driver. High frequencies above 3.5kHz are handled by ATC’s SH25-76S Dual-Suspension 1/25mm soft dome tweeter. This HF driver update is the primary improvement from the Mk1-to-Mk2 model. The enclosure is a ported/vented type, tuned to 32Hz and featuring a 3/75mm diameter port with flared entry & exit to minimise port air noise.

The SCM25A Pro Mk2 is actively driven by a 3-way class A/B amp pack mounted in the rear of the cabinet. Each drive unit has its own dedicated power amplifier. Audio input is via a rear panel mounted 3-pin female XLR and power via an IEC mains power inlet. There are user controls for input sensitivity and bass ‘boost’. Crossovers are 4th order Linkwitz-Riley and all-pass filters are included to optimise the phase response through the crossover regions, improving the tonal accuracy, imaging, on and off-axis frequency response. FET peak limiters are included to reduce amplifier ‘hard-clipping’. Power ‘on’ and limiter ‘active’ is indicated by a front panel mounted bi-colour LED.

Product Details

  • 3-way design featuring ATC SM75-150 Soft Dome mid-range driver
  • Wide dispersion vs frequency for excellent stereo imaging over a large listening area
  • ATC discrete MOSFET class A/B amp-pack delivers high dynamic range in combination with very low distortion and an extended HF bandwidth
  • 4th order active crossovers with all-pass phase compensation ensure outstanding driver integration
  • Input sensitivity and bass ‘lift’ user controls
  • Hand-built in England
  • 6-year warranty
Drive Units
Bass: 1 x SB50-164SC 8Ω, Mid: 1 x SM75-150 16Ω, HF: 1 x SH25-76S 6Ω
Low Frequency Cut-off (-6dB, anechoic)
47Hz
High Frequency Cut-off (-6dB)
25kHz (-6dB)
Max SPL
109dB continuous / 115dB peak (Per pair, IEC Weighted Pink Noise, 1m, anechoic).
Sensitivity
+4dBu ref 92dBC (Bass Boot 0dB, Input Sensitivity 1V, Pink noise).
Balanced Input
1 x Rear Panel Mounted Female XLR, pin 2 hot.
Input Impedance
20kΩ (differential).
Input CMRR
> 82dB (10kHz).
Input Sensitivity
2.2dBu / 1Vrms for full power, control: Continuously Variable from 2.2dBu – 8.2dBu / 1Vrms - 2Vrms (-6dB)
Bass Boost Control
Continuously variable from 0dB to +3dB.
Crossover Filters
4th Order Linkwitz-Riley at 380Hz and 3.5kHz.
Frequency Response
< 2Hz to > 200kHz (-3dB).
Amplifier type
Grounded Source MOSFET based Class A/B, convection cooled.
Output Power
Bass: 150W (8Ω), Mid: 60W (8Ω), HF: 32W (6Ω)
THD+N
< 0.003%/-92dB (1kHz, 1dB below rated power, 90kHz BW)
Limiter
ATC Active FET Momentary Gain Reduction, limiter ‘active’ indicated via front panel LED.
Mains Input
220-230V or 115V
Power Consumption
Idle 24W/35VA. 1/8th Power 117W/159VA. Full Power 255W/324VA.
Heat Output
Idle 82BTU/hr. 1/8th power 335 BTU/hr. Full Power 358BTU/hr.
Weight
25.1kg
Dimensions (H x W x D)
271 x 430 x 411 mm