ATC - USA SCM20ASL Active Monitor Speakers

ATC SCM20ASL Active Bookshelf Speakers Key Features:

• 150mm/6" ATC 'Super Linear mid/bass driver loaded in a compact sealed cabinet.
• 25mm/1" ATC 'S-Spec' soft-dome dual-suspension HF driver.
• On-board ATC active 250W 'Amp Pack' module.
• Balanced input & 2nd order Linkwitz-Riley active crossovers.
• User adjustable input sensitivity & bass shelf controls.
• 2 x class A/B MOSFET amplifiers, 200W bass/mid & 50W high frequency.
• Hand-built in England.
• 6-year warranty.
• Available in natural or gloss finish.

Product Description:

The active SCM20ASL is equipped with an integrated 250W Amp Pack, ready to pair with a high-quality pre-amplifier, DAC/pre, or streaming pre-amp for exceptional performance.

Instead of relying on a passive crossover and an external power amplifier, the SCM20ASL uses a precisely matched Amp Pack mounted on the rear of the cabinet. Its electronic architecture features a balanced input feeding a 2nd-order active crossover, which then drives two dedicated Class A/B power amplifiers—each optimized for the mid/bass and high-frequency drivers.

This active approach ensures improved accuracy in level and timing, while the direct coupling of the amplifiers to the drive units delivers superior control and greater dynamic range compared to a traditional passive design.

The cabinet is engineered for rigidity and low resonance, combining internal bracing with damping materials to suppress vibration. Bitumastic panels are strategically applied to further minimize coloration, and the speaker is available in a range of premium finishes.

Acoustic Specifications:

Mid/Bass driver

1 x 150mm/6", SB75-150SL 8Ω

High Frequency Driver

4 - 92,000 Hz

Power Consumption in Standby

1 x 25mm/1", SH25-76S 6Ω

Low Frequency Cut-off

55Hz (-6dB, anechoic)

High Frequency Cut-off

25kHz (-6dB) Matched Response: +/-0.5dB Crossover Point: 2.2kHz MaxSPL: 108dB continuous, 114dB peak (per pair, IEC Weighted Pink Noise, 1m, anechoic)

System Sensitivity

85dBC SPL (@1m, pink noise, -18dBu, 1V input sens. 0dB bass boost)

Electronic Specifications:

Balanced Input

1 x Rear Panel Mounted Female XLR, pin 2 hot Input Impedance: 20kΩ (differential)

Input CMRR

>60dB at (10kHz)

Input Sensitivity

2.2dBu/1Vrms for full power Input Sensitivity Control: -6dB switchable, -6dB variable. Total adjustment 2.2dBu/1Vrms to 14.2dBu/4Vrms

Bass Shelf

-2dB to +3dB, switchable in 1dB steps Crossover Filters: 2nd Order Linkwitz Riley

Amplifier type

Grounded Source MOSFET, class A/B, convection cooled

Output Power

Bass 200W (8Ω), H.F. 50W (8Ω) THD+N: <0.0017% /-95dB (1kHz, 1dB below rated power, 90kHz BW) Frequency Response: <2Hz to>200kHz (-3dB)

Limiter

 ATC Active FET Momentary Gain Reduction

Electronic amp protection

Amplifier d.c. offset and over-temperature (both indicated by rear panel LED) Mains Input: 220-230V or 115V, factory set. Please observe panel markings and labels!

Power Consumption

Idle 26W/41VA. 1/8th Power 116W/116VA. Full Power 312W/398VA

Heat Output

Idle 89BTU/hr, 1/8th Power 311BTU/hr, Full Power 382BTU/hr

Physical Specifications:

Net Weight

24.3kgs/53.6lbs

Dimensions

HxWxD 450x250x411mm 17 11/16" x 9 13/16" x 16 3/16"