ATC SCM20ASL Classic Flagship Bookshelf Speaker

ATC's flagship 2-way stand-mount loudspeaker

The SCM20ASL is a 2-way active stand-mount loudspeaker and is the ideal choice in modestly sized rooms where exceptional musical reproduction is the goal.  Its sealed cabinet design ensures well controlled, clean bass playback, even in smaller spaces and/or when located close to walls.  The bass driver, HF driver and amplifier are all designed and manufactured in-house by ATC and to the highest standards to form a system that is hard to match with a passively driven system.

Input to the loudspeaker is via rear panel mounted balanced XLR (but the input can be driven from an un-balanced output if needed).  There are user controls for input sensitivity and low frequency shelf cut/boost.  The input sensitivity control allows the user to tailor the input gain to suit their source/pre-amplifier combination, reducing noise and optimising volume control operation.  The low frequency shelf control gives the user the option to subtly adjust the bass response to suit their room, loudspeaker postion, and/or their personal taste.

The loudspeaker crossovers are active, analogue, 2^nd order Linkwitz-Riley and an all-pass filter is included to optimise the phase response through the crossover region, resulting in far improved tonal balance and stereo imaging.  Power is provided by on-board class A/B MOSFET power amplifiers, capable of delivering 200W and 50W continuous power to the bass and HF drivers respectively.  The speaker is supplied with a removable grille, wrapped in acoustically transparent cloth.

Overview
The SCM20ASL is a 2-way active stand-mount loudspeaker and is the ideal choice in modestly sized rooms where outstanding musical reproduction is the goal. Its sealed cabinet design ensures exceptionally well controlled bass, even in smaller spaces and/or when located close to walls. The bass driver, HF driver and amplifier are all designed and manufactured in-house by ATC and to the highest standards to form a system that can’t be matched by equivalent passive systems. The bass driver is a 6”/150mm part with large 3”/75mm voice coil and short-coil (long-gap) motor assembly featuring ATC’s proprietary ‘SL’ motor technology which, reduces distortion in the upper bass and mid-range. High frequency reproduction is handled by an ATC 1”/25mm soft-dome part featuring a dual-suspension and very high energy 2.1 tesla motor. Integrating the two drive units is a precision active crossover which feeds a pair of class A/B MOSFET power amplifiers. The crossover operates at line-level maximising efficiency, plus the inclusion of an allpass-filter results in improved timing and tonal balance through the crossover region. One power amplifier is dedicated to each drive unit and their performance and power output is carefully tailored to the driver demands and the musical elements they reproduce. The SCM20ASL cabinet features a combination of bracing for stiffness and damping to supress resonance and is available in a wide range of real wood veneers, satin black or white painted finishes and high gloss lacquers.

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.

Standard Finishes: Rm45,900
Premium Finishes: Rm51,500
Add for High Gloss Lacquer over Veneer: Rm11,300
Piano Black or White: Rm55,400
Other / Custom finishes: P.O.A.

ACOUSTIC SPECIFICATIONS

Bass/mid driver: 1 x 150mm/6”, SB75-150SL 8Ω

High Frequency Driver: 1 x 25mm/1”, SH25-76S 6Ω

Low Frequency Cut-off: 55Hz (-6dB, anechoic)

High Frequency Cut-off: 25kHz (-6dB)

Crossover Point: 2.2kHz

MaxSPL: 108dB continuous, 114dB peak (per pair, IEC Weighted Pink Noise, 1m, anechoic).

Sensitivity: +4dBu rev 95dBC (Bass Boost 0dB, Input Sensitivity 1V, Pink noise).

ELECTRONIC SPECIFICATIONS

Balanced Input: 1 x Rear Panel Mounted Female XLR, pin 2 hot

Input Impedance: 20kΩ (dif ferential)

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. of fset 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. ¹/₈ Power 116W/116VA. Full Power 312W/398VA

Heat Output: Idle 89BTU/hr, ¹/₈ Power 311BTU/hr, Full Power 382BTU/hr

PHYSICAL SPECIFICATIONS

Net Weight: 27kgs/59.5lbs

Dimensions: HxWxD 450x250x425mm 17 ¹¹/₁₆” x 9 ¹³/₁₆” x 14 ³/₁₆”