ATC originally made its mark in professional recording studios. In 1974 Billy Woodman created ATC and began manufacturing a 12-inch driver that could handle more power and produce less distortion at higher SPL levels than existing drivers. ATC soon followed the 12-inch driver with a soft dome midrange driver in 1976, and then complete speaker systems soon thereafter. During the intervening 40 years, ATC has expanded into powered and active speakers, as well as standalone electronics.
Today's review will concentrate on one of ATC's least expensive and smallest consumer speakers, the SCM7 ($1,499/pair). This two-way system was designed for nearfield and small-room listening, and it combines ATC's legendary ability to play loudly with low distortion with a small footprint that can fit into a tight space easily. Given that consumers have more choices in small monitor speakers than any other speaker category, the ATC SCM7 faces some tough competition. Let's see how it fares.
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The SCM7 isn't a new model; this third version, named the mark III, has been completely redesigned. It features ATC's new SH25-76 25mm soft dome tweeter that uses a special dual suspension system that suppresses rocking modes, as well as a short edge-wound voice coil in a long narrow magnetic gap to eliminate the need for ferrofluids for cooling. With a 15,000 gauss (1.5 tesla) neodymium magnet, a precision-machined 5.5mm rigid alloy waveguide, and a heat-treated top plate that increases heat dissipation, the SH25-76 tweeter delivers (according to ATC) "optimum dispersion, flat on-axis frequency response, and resonance-free operation." The SCM7's midrange/woofer is 125mm (five inches) in diameter and uses a 45mm (two-inch) soft dome with a 3.5kg magnet system and a 45mm flat-wire voice coil. The magnet system and carefully weighted and doped fabric cone contribute to the driver's overall performance, which is aimed at creating a speaker with excellent horizontal dispersion, wide bandwidth response, and convincing bass response.
The biggest physical difference between the second- and third-generation SCM7 is its cabinet shape. Instead of the fairly standard box used by the mark II, the mark III's cabinet has curved sides to reduce internal resonances and increase overall cabinet rigidity. Another external difference is the mark III's magnetic grill cover attachments instead of the old-style, push-in kind. This makes for a much cleaner look when the grills are removed as well as far quicker and easier attachment and removal. The back of the SCM7 has two pairs of five-way binding posts that can be bi-wired if you wish.
Unlike many small monitors that rely on a port or vent to augment their bass response, the SCM7 is a sealed cabinet. The advantage of not using a port is that it eliminates the group delay issues and phase anomalies that a port creates. This makes it much easier to blend the SCM7 seamlessly with a subwoofer. Instead of producing a mid-bass hump, the SCM7's bass rolls off smoothly with substantial output down to 70 Hz.
The Hookup
During most of the review, the ATC SCM7 speakers were situated in my nearfield desktop system because that is their intended primary application. ATC has a whole slew of larger speakers, such as their SCM11, that are better suited for room-based applications (unless your room is very small). In order to get the speakers set up so that my ears were on a horizontal plane between the tweeter and midrange/woofer, I used a pair of closed-cell, high-density "stands" that I made, as well as a pair of Ultimate Support adjustable speaker platforms to raise and angle the speakers so they were parallel with each other. After trying them at various angles varying from pointing straight forward to a 45-degree angle, I opted for about a 40 degrees of angle (according to the Genelec Speaker Angle app).
I used several different power amplifiers with the ATC SCM7 speakers, including the Wyred4Sound mAMP, the April Music Eximus S1, and the little Olasonic Nano-UA1 integrated amplifier. Even though the SCM7 speakers are only rated at an 84dB efficiency and the Olasonic only puts out 26 watts into four ohms, this combination generated adequate volume levels on commercial material for a desktop or even a small-room environment. On my own recordings, which have a lower overall volume level than most commercial releases, at times I longed for more output from this combination, especially during FFF (triple forte) passages, when the Olasonic just ran out of juice.
Although the SCM7 speakers had adequate bass output down to 70 Hz in my desktop system, if you require further bass extension, the use of a subwoofer is recommended. I coupled the SCM7 speakers with a Velodyne DD10+ subwoofer. Crossing over from the SCM7 speakers to the subwoofer at 70 Hz delivered a smooth transition from the monitors to the subwoofer. For part of the review period, I used the crossover to reduce the bass sent to the SCM7s, but most of the time I let the SCM7s bass roll off naturally with no additional bass attenuation. Obviously, one way to increase the SCM7's power handling would be to use a crossover to reduce the bass directed to the SCM7s, but this can also reduce transparency because of the additional circuitry and cabling. Also, because the SCM7 speakers have such extended power handling, the need to shield them from having to cope with low bass frequencies is reduced, especially when compared with other similarly sized small monitors.
Click on over to page 2 for the Performance, the downside, the competition and comparisons, and the conclusion . . .
Performance
Having had a pair of ATC SCM7 mark IIs as part of my collection of small reference monitor speakers for several years, I was quite familiar with the SCM7's sonic character. While both versions of the SCM7 share a similar level of dynamic exuberance, the new mark III design equals or betters its predecessor in all sonic parameters. Of course the mark III's harmonic balance is quite similar to the mark II, yet it sounds less mechanical and more natural. I appreciated the SCM7 mark II's overall presentation, but after a full day of listening, I often would switch to something slightly more euphonic, such as the Silverline Minuet Supreme monitors, for evening listening. With the SCM7 mark III speakers, though, even a full day of listening at moderately high volume levels didn't generate any desire to change speakers. The mark III speakers remind me of the ProAc Anniversary Tablettes ($2,200/pair U.S.) in that they are both highly resolving yet relatively unfatiguing, making each of them an ideal nearfield reference transducer.
Like its predecessor, the SCM7 mark III delivers outstanding inner detail and overall resolution. Situated on my desktop, the SCM7 equaled the exemplary low-level resolution of the Audience 1+1 speakers. On my live-concert Boulder Philharmonic Orchestra recordings, the SCM7 III rendered spatial and dimensional details with spot-on accuracy.
Since no transducer, be it a speaker or a pair of headphones, is completely neutral, the question is always on which side of the neutrality line does a particular pair of speakers reside? I would put the ATC SCM7 mark III speakers on the ever-so-slightly warm side of neutral, not because of excess midbass or lack of top-end air, but because the SCM7's lower midrange adds an extra dollop of warmth to its sound. I wouldn't call this additive coloration as much as a "seasoning" wherein the lower midrange has a bit more gravitas and richness that the previous generation of SCM7.
Certainly one of the SCM7 III's strong points is its dynamic acuity. Over the years, I've auditioned plenty of small desktop-capable speakers, and few have exhibited the dynamic range and contrast of the SCM7. Among my stable of reference small-footprint speakers, only the Aerial Acoustics 5 B captures the same dynamic range as the SCM7 III. Both speakers manage to make triple fortes louder than fortes without sounding stressed in any way.
Since the ATC SM7 III speakers are a sealed enclosure design without any ports, vents, passive radiators, or other bass augmentation technologies, the bass roll-off is very smooth and well-controlled without any humps, bumps, or other non-linear frequency-response characteristics. It was easy to mate them to a subwoofer.
The Downside
No loudspeaker is perfect. While the ATC SCM7 speakers are excellent all-round nearfield monitors, they do not excel over other small monitors in every performance category. The SCM7 speakers do not create quite as large a listening area or "sweet spot" as the Audience 1+1 speakers ($1,800/pair). Also, as you move outside the primary listening position, the SCM7's frequency balance and imaging shifts more noticeably than that of the Audience "The One" ($995/pair) or the Audience 1 + 1 speakers.
Since they have a sealed enclosure, the ATC SM7 speakers don't have as much low-frequency extension or output as some ported designs. If your listening room doesn't permit the use of a subwoofer and you favor bass-heavy music, you may want to think about moving up to the SCM11, which has a larger enclosure and bigger midbass driver...or try a speaker like the Silverline Minuet Supreme ($600/pair), which has a ported design that delivers more midbass boost.
Competition and Comparison
Compared with the Audience 1+1 ($1,800/pair), which is one of my current favorite nearfield monitors, the SCM7 has a bit more upper-frequency life and energy in the 1.5-to-3kHz region. The SCM7 demonstrated slightly more overall dynamic contrast, especially during triple forte passages. The Audience 1+1 bettered the SCM7 in its portrayal of three-dimensionality and retention of subtle spatial cues. The Audience 1+1 also had a larger sweet spot with less harmonic and spatial shift as the listener moves outside the speaker's sweet spot listening area.
The Aerial Acoustics 5B ($2,495/pair U.S.) have a noticeably lusher harmonic balance than the ATC SCM7 speakers, and they have more bass extension. But the 5Bs do not disappear quite as well when used nearfield (there are some diffraction effects off their larger front baffle) as the SCM7s. While both speakers do an excellent job of delineating subtle and low-level details, and both can handle higher-powered amplifiers and high SPLs without issues, the Aerial 5Bs have a slightly more laidback spatial presentation.
Although it's been several months since I've had the ProAc Anniversary Tablette speakers ($2,200/pair U.S.) in my desktop system, comparing my notes on the Tablettes with the SCM7s, I was struck by the number of similarities between the two speakers. Both excelled at dredging up fine details buried deep within the mix, and both did it in a musical and unfatiguing manner. The Tablettes may have a trifle more midbass energy than the SCM7s, but they both rank highly in my personal pantheon of excellent two-way nearfield monitors.
Conclusion
Yes, there are many small-footprint speakers that can serve as nearfield desktop monitors. As their prices escalate into four figures, the quality and performance of quite a few small monitor speakers evolves to the point where they can easily compete with and often exceed the sound quality available from a comparably priced floorstanding room-based system. The ATC SCM7 mark III monitor is one of the best two-way nearfield monitors I've heard. And while it doesn't completely overpower the competition in all performance categories, the SCM7 certainly achieves a high-level overall sonic performance that puts it on a par with anything I've heard under $2,500.
If you are in the market for a small monitor speaker capable of wide dynamic contrasts, accurate imaging, and well-above-average power-handling capabilities, the ATC SCM7 mark III speaker should be on your short list of must-audition transducers. And if you already own the previous version of SCM7 speakers, I would strongly suggest that it might be time for an "update" to the latest version. If you liked the SCM7 mark II, you are going to love the SMC7 mark III.
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2022-06-25 19:36:46
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