Floorstanding loudspeakers — ATC SCM150SE

The SCM150SE is the Special Edition of the SCM150 active tower from ATC, the English company that hand-builds its loudspeakers at Aston Down in Gloucestershire. It belongs to a group of SE models that also covered the SCM50SE and SCM100SE, and ATC now lists it among its legacy editions. Compared with the standard SCM150ASLT, the SE has a taller and wider cabinet topped by a decorative brow, and it was sold in active and passive versions.

Key specs that matter

Drive units are ATC's SH25-76S soft dome tweeter of 25 mm, the SM75-150S soft dome midrange of 75 mm and the SB75-375SL bass driver of 375 mm, which uses a short coil in a Super Linear magnet system. The crossover points are 380 Hz and 3.5 kHz. Response holds within 2 dB from 60 Hz to 17 kHz, and the minus 6 dB limits sit at 25 Hz and 25 kHz. Maximum output is 117 dB, dispersion spans plus or minus 80 degrees across and plus or minus 10 degrees vertically, and pairs are matched to within 0.5 dB. Amplifier power totals 350 W, with 200 W for bass, 100 W for mid and 50 W for treble. The active cabinet measures 1205 x 533 x 634 mm (HxWxD) and weighs 97 kg.

Engineering and use context

A fully discrete amplifier drives each of the three units, and together they form a tri-amplifier that also carries active crossover filters, phase correction and overload protection. Input is a single female XLR per speaker. ATC lists the SH25-76S as a new tweeter that it designed and built in-house. The brow above the baffle comes in three combinations - a black acrylic centre section with red acrylic horns, a veneered centre section with dull nickel horns, or black acrylic for both. Veneers include cherry, walnut, oak, black ash, rosewood, European crown cut walnut, burr walnut, burr magnolia, pippy oak and burr poplar, with satin black and satin white paint and high gloss lacquer as options. The passive SE uses a 640 mm deep cabinet, weighs 93 kg, is rated at 91 dB at 1 W and 1 m and accepts amplifiers from 100 to 1500 W. ATC backs the model with a 6-year warranty.

Pairing

As an active loudspeaker the SCM150SE accepts balanced line level directly from a preamplifier, and ATC names its SCA2 preamplifier as the matching partner. Sources with only single-ended outputs will need a preamp or DAC stage that provides balanced XLR connections.

Alternatives

The SCM50SE is the smaller three-way Special Edition tower from ATC, using a 234 mm bass driver in a 1045 mm cabinet that weighs 64.5 kg.