ATC SCM7

Hardware Review

ATC SCM7
Monday, October 19, 2020
standmount loudspeaker
Trevor Butler

To have the SCM7 two-way bookshelf as an entry model in an expansive range speaks volumes about ATC’s ability to create natural-sounding loudspeakers which are not only British designed but also British built and based on their own, proprietary drive units. This company has gained a formidable reputation in both professional and hi-fi circles, and rightly so to my mind. It was formed in 1974 by pianist and Australian engineer Billy Woodmann to make custom drive units for the professional sound industry. Quickly making its mark with a driver capable of handling more power and generating less distortion than anything else available, it was just two years later that ATC’s ground-breaking soft-dome midrange drive unit was unveiled. Here was a technical tour-de-force which became a firm favourite among many working in recording studios and sound reinforcement. It not only boasted a more uniform dispersion over a wider frequency range, but did so with much lower distortion than was believed achievable at the time. ATC went on to redefine studio monitoring with this driver which was chosen to mix ‘big name’ bands including Sting, Pink Floyd, the late Lou Reed and Supertramp. This is why many believe it to be the ultimate midrange transducer. Little wonder then that it has been constantly revised and updated since that time.

I still recall fondly the pair of SCM10s, in stunning piano black, which I acquired during my time on Hi-Fi News magazine. Stupidly, I lent them to an acoustician who promptly damaged them beyond repair. I have missed them ever since. At the annual audio extravaganza that was the Penta Show, I would rely on a pair of active SCM 50 three-ways for public demonstration of one audio technique or another: one year it was Ambisonics, another German DAB radio via satellite, both seemed revolutionary at the time. 

Technology
More recently, ATC’s boffins have created a soft-dome tweeter as a replacement for the previously used third-party unit. This was carefully conceived with dual suspension, and hand-built at ATC’s headquarters in Gloucestershire. We find a 25mm version in the SCM7 along with a precision shallow waveguide, this is coupled with a 125mm (5-inch) mid/bass driver with integral soft dome. The speaker itself has gone through several iterations since it was first launched, each time being honed and tweaked for better sound quality. It comes in below by beloved SCM10 and at a price I can hardly believe. It does turn out to be something of a bargain.

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The seven litre cabinets are rather ‘dinky’ in appearance (their volume giving the model its designation) and measure just 30cm high with a pleasing curvature to the box. While the standard finish options of cherry or black ash offer real value-for-money. Small they maybe, but lightweight and flimsy they certainly are not, partly due to the 3.5kgs of the huge, underhung magnet system on the mid/bass unit with its 45mm voice coil. These are no snap-together boxes as is often found at this size and price-point, rather high-quality, precision cabinets which are heavily damped and sport bi-wire terminals. Their design allows them to be used quite close to the rear wall and I found that a very slight toe-in towards the listener provided the optimum balance. I opted not to use the magnetic grilles, purely because I did not need to and because I preferred the veneered look. 

The crossover network is worthy of note, employing as it does a second-order filter for both the low-pass and high-pass sections. The LF section also has an R-C Zobel network which corrects the bass unit’s rising impedance for the benefit of the low-pass network. In the HF section, a resistive T-attenuation network reduces the tweeter’s output to match the bass level. Inductors throughout are air-cored, with capacitors used being 250V DC metalized polyprop types. This attention to detail speaks volumes of ATC’s considered design approach, even to entry-level products such as the SCM7.

Sound quality
Knowing that passive ATCs traditionally need plenty of oomph to be driven properly, and noting that this the SCM7 is a sealed-box (infinite baffle) design, I began by hooking them up to my trusty Hegel H190 (a £3,000 streamer, DAC and integrated amp), sitting the diminutive speakers on some appropriate stands so as to bring the tweeter up to ear-level when seated. Part way through the review period, Hegel’s new H95 arrived and, at £1,500 seemed a more realistic pairing. The reduction in power did little, if anything, to reduce the dynamics and showed just how easy the SCM7s are to drive given their modest 84dB sensitivity. 

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My initial notes were of a pleasing, natural sound reproduction with great imaging and good dynamics. The midrange appeared slightly pronounced but not in an unpleasant way. These are small speakers and the scale reproduced tended to reflect this, more with a reduced height than width. This is clearly a well-designed loudspeaker, as is expected from ATC, and offers amazing value-for-money. Quite how so much can be offered for so little in a UK designed and UK built speaker is incredible. It puts many other brands to shame if I’m honest. 

In detail, the quoted -6dB point of 60Hz was audibly achieved and, being no bass junkie, I was well satisfied with the LF performance. Given the closed-box design, one could easily add a sub-woofer if required (there is the ATC C1) but at no time did I feel it necessary given the likely listening space they will typically be used in. That sealed-box also ensures a smooth bass roll-off which is well-controlled and without any audible bumps or humps. That said, bass fans listening in tight spaces might consider moving up to the slightly larger SCM11 model. 

I also obtained excellent results from the SCM7 when listening to them in the near-field, and closer than I would ordinarily even for a speaker of these dimensions, which reveals their studio monitor heritage. Indeed, they seemed even more accurate and involving in the ‘close-up’ position. Many will know that I listen to a lot of human voice, often the acid test of a loudspeaker’s ability. Here the SCM7 scored very highly with a totally realistic and generally natural reproduction of source material. 

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Live performances tended towards the sublime, with outstanding levels of inner detail revealed along with convincing spatial and three-dimensional details as in an enjoyable listen to Beethoven’s Seventh Symphony, recorded with the Berlin Philharmonic in 1953 and the Leonore Overture  No.3, recorded with the Vienna Philharmonic in the Musikvereinsaal back in June 1944. The characteristic high voltage dynamism swept me along from the from first to last. With rock and pop, as well, the foot-tapping ability of the little SCM7s entertained with the likes of Cyndi Lauper’s studio album True Colours which revealed the speaker’s gravitas and richness thanks to a slight warmth through the middle registers.

Conclusion
Addictive is the word I would use to describe the SCM7. I lived with them quite happily for many weeks and found them highly enjoyable whatever I asked them to do. The imaging prowess is impressive, the bass surprising given the size of sealed enclosure, and the get-up-and-go means they are endearing to music lovers with a variety of tastes. Their ability to deliver accurate speech reproduction was a huge bonus, but they will equally impress those constrained by size or price and can be highly recommended. In fact the price makes them a genuine bargain. 

Specifications: 

Type: Infinite baffle two-way standmount loudspeaker
Crossover Frequency: 2.5kHz
Drive Units:
Mid/bass – 125mm with integral soft dome
Tweeter – 25mm soft dome
Nominal frequency response: +/ -6dB 60 – 22,000 Hz
Nominal impedance: 8 Ohms
Connectors: bi-wire binding posts
Sensitivity: 84dB 1w/1m
Dimensions HxWxD: 300 x 174 x 215mm
Weight: 7.5kg
Finishes: cherry, black ash, satin black, satin white
Warranty: 6 years

 
Price: 
£875
Manufacturer Details: 

Loudspeaker Technology Ltd
T +44 (0)1285 760561 
www.atcloudspeakers.co.uk