ATC EL50 Anniversary active speakers
ATC saves the EL appellation for its most ambitious designs and has used it only once in the past for the EL150 in 2006. For the EL150 and the new EL50, ATC has dropped a conventional box design, typical of ATC’s pro and domestic ranges, for something more elegant and sophisticated. It’s not just a looks thing, the tall but shallow curved cabinet was conceived with sound quality in mind, as is always the case with this brand, but given that the company has recently celebrated its 50th year, they decided to make the EL50 Anniversary as alluring as they could.
The EL50 is an elliptical (EL) section speaker that stands at over 1.4 metres (nearly 56 inches) high and weighs 63 kilos, yet it is only 24cm (9 inches) deep, which makes it relatively easy to accommodate. Its curved sides are created with vacuum formed plywood for maximum stiffness and minimal diffraction. Diffraction is usually produced by sharp cabinet edges, which cause sound to bounce off and diffuse the acoustic image. Apparently, you need a radius of between half and quarter of a wavelength to avoid this, and here the radius of the curves is 150mm, which is effective from the midrange upwards.
The Super Linear drive units in the EL50 are pretty much the same as those found in a conventional ATC SCM50 loudspeaker and consist of a 25mm soft dome tweeter, a 75mm soft dome midrange and a 234mm (9 inch) bass driver. Cabinet aside what makes the EL50 special is its electronics. Again, as per all ATC active 50s the Class A/B MOSFET amplification consists of 50W for the treble, 100W for the mid and 200W for the bass driver, but for the EL50, each has its own linear power supply. In other words, there are three power transformers hidden in the elegantly curved metalwork at the back of the ‘box’ rather than the usual one with secondary windings.
While the power ratings haven’t changed, the circuit boards are now populated with surface mount devices (SMD) rather than through-hole components. This is something that ATC are phasing in across their active speaker range, but sadly none will benefit from the multiple power supplies included in the EL50.
Consequently, the electronics in the EL50 are the most sophisticated that ATC have incorporated in an active loudspeaker, with lower noise and distortion than even their most expensive designs to date. The inclusion of a separate power supply for each of the three power amplifiers per side is a major step forward that one would expect to bring significant rewards in terms of sound quality. I can tell you now that those expectations have been exceeded.
It’s probably worth reiterating that an active loudspeaker has a significant advantage over a passive one inasmuch as the power amplifier doesn’t have a crossover between it and the drive unit it’s trying to control. Not only that, but there is one amplifier per drive unit, so the potential for control is an order of magnitude greater than with passive designs. The only potential fly in the ointment is the electronic crossover. For an active design to benefit from its potential advantages, the crossover has to be a very low noise device with minimal colouration. Fortunately, ATC have several decades of experience when it comes to designing such things and the latest switch to SMD should improve matters still further.
The back panel on the EL50 offers a balanced input on XLR and variable input sensitivity between one and two volts. This makes it easier to match the speakers with the preamplifier being used. I found that with a Music First transformer passive pre, the higher sensitivity 1V option worked best. There are also trigger connections for those not wanting lean down and find the power switch by feel. As this is close to the floor I can see the appeal; unfortunately, passive preamps don’t have trigger outputs.
The EL50 stands on an oval plinth, which is supported on machined aluminium outrigger feet. These are necessary for stability and can accommodate the supplied spikes if required – quite nicely made spikes at that – but they were left in the box. It should be mentioned that these ATCs have particularly beautiful walnut veneer finish that is matched one side to the other. This and a deep gloss lacquer, plus leather inserts down the middle and over the angled top of the cabinet, make for a very classy looking speaker.
Sound quality
The EL50 proved to be one of, if not the most, convincing loudspeakers I have had the pleasure of reviewing in nearly 40 years. The degree of insight that it gives into familiar, often long-term favourite recordings is phenomenal, even in comparison to more expensive amp/speaker combinations. I lived with SCM150 ASL actives for quite some time, but they did not have the resolution on offer here, thanks to the high rigidity and low diffraction nature of the cabinet and the changes made to the amplifiers. These upgrades have brought a degree of refinement that I have not encountered in an active design.
Even the best active speakers have characteristics of the breed: even the tiniest distortions become audible because the amplifier is directly connected to the drivers. In other words, the amps have to be at least as clean as the best standalone examples for their shortcomings not to be magnified. The amps in the EL50 are clearly superior examples, so these ATCs don’t sound like active speakers in any negative sense of the word. They don’t have obvious grip, the high frequencies are devoid of fine grain and you don’t feel tired after a long listening session. Instead, you hear a lot more of the signal than is usually the case. When this is combined with the phase accuracy that active operation provides, the results can be shocking.
Quite a lot of the music I played through the EL50s turned out to have physical dimensions that are rarely hinted at in more conventional high-end amp/speaker pairings. This means that the extent to which the efforts of individual musicians can be appreciated is simply staggering. For instance, on the live version of No Quarter (Led Zeppelin, The Song Remains the Same) the keyboards, bass and drums are providing such a dynamic and engaging backing that Jimmy Page could have been doing almost anything on his guitar and it would have sounded glorious. The whole thing is awesome of course, but when you can hear so much shape in every instrument and the bass pedals are as powerful and clean as this, the effect is tantamount to being in the best seat at Madison Square Garden over 50 years ago. In fact, I would wager that thanks to work done in the mixing and mastering, no one got as good a sound as this at the actual event, but they did get to see a great band at close to the peak of its powers, which is some compensation!
The EL50’s phenomenal resolving powers are brought to bear on everything played, including MOR classics like It Keeps You Runnin’ by the Doobie Brothers, complete with the outstanding voice of Michael McDonald and backing vocals that are to die for. Here there’s a huge amount of dimensionality to the various instruments and voices, and acres of depth in the recording. It has a physicality that is beyond expectation, and this is a song I have been playing on big systems since the nineties.
You need a good system to appreciate the full potential of the EL50 and I was fortunate enough to get hold of a Cinnamon Galle DAC as well as a new Muon 2 network switch from Network Acoustics whilst the speakers were in the system. I also borrowed an ATC SCA2 preamplifier to try instead of the Music First Baby Reference that informed most of my observations, the latter delivering a more open sound while the SCA2 brought focus and power. Both worked extremely well.
I expected the transition from the EL50s back to my regular speakers to be difficult, but was not ready for just how vague everything sounded when I did so. The pinpoint position and solidity of Stephen Still’s voice on So Begins the Task (solo on Carry On) that the ATCs produced suddenly became almost flat and blurry. And no amp speaker combo that I could muster got close to the control and definition of the EL50. This is an area where actives have a natural advantage of course and in practice it can mean that bass seems leaner than it actually is, but the control provided means that you are hearing a more realistic rendition of what was laid down in the studio or on the stage.
The more music you play the more obvious this becomes, but then the aforementioned bass pedals on No Quarter come along and the bass has power and body aplenty. It is truly awesome.
Traditionally, ATCs tend to focus on delivering the signal in the style of a professional monitor, that being the original intent of their design, and in this respect other speakers can compete with a more open, airy presentation. With the EL50s though, there are big differences in openness from one recording to another and this gives the sense that what you are hearing is genuinely accurate. It can mean that certain pieces of music don’t have the height and width that you’d expect, but the fact that so much detail is in evidence suggests that that sense of airiness might be a characteristic of the speakers that produce it.
Nor do you have to wind up the level to appreciate what the EL50s do. Studio monitors have a tendency to sound better at high levels and the EL50s do work extremely well under such circumstances, but they also deliver the goods at moderate volume. High-res favourites like The Byrds are spectacular with their elaborate production, but Crosby, Stills and Nash’s Guinevere has more atmosphere still, the relative simplicity of the recording, plus its analogue origins, having more low-level detail to reveal, and these ATCs relish digging it out. A relatively contemporary live recording: Bill Frisell’s East West, flabbergasted me with its three dimensionality. This is an album that I have been immersed in for a couple of years now but the degree of shape and nuance revealed through the EL50s is truly next level. I was so impressed with the track Los Angeles Blues that the crowd’s response seemed totally inadequate: given the performance, they should have been screaming the place down. That’s the problem with us jazz fans, we can be a little too reserved.
One more thing that really impressed is that while the EL50s are very revealing they don’t highlight the shortcomings of lesser recordings too obviously. There are more than a few starkly revealing speakers that require only the slickest productions and high-res files to make them sound good, but that is not the case here. The wailing of Ian Gillan on Child In Time gets a bit much, but that’s because he sounded like that back in the day. If you love that music you will find nothing to criticise.
Conclusion
The ATC EL50 is a fitting celebration of the brand’s first 50 years. It looks spectacular and sounds significantly better than it looks. I would go so far as to say that you would be hard pressed to find a loudspeaker and amplifier combination that could compete on just about any level. Whether you would agree will depend on taste to an extent, but if accuracy is what you are after, if you want to hear precisely what the artists/producer/mastering has achieved, taste should take a back seat: when you exercise your taste in the choice of music, the sound should be as close as possible to that heard on the monitors at the recording.
ATC makes both professional and domestic loudspeakers but does not ‘voice’ the latter in an effort to impress potential customers. In both instances accuracy is the goal and in the case of the EL50 Anniversary, that accuracy has been raised higher than you are likely to find anywhere, regardless of price. The search is over for the least coloured, highest resolution amplifier and loudspeaker combo. I hope that someone can do better but won’t be holding my breath while I wait.
Pros
Exceptional resolution and insight into recordings
Highly accurate, studio-grade presentation with minimal coloration
Powerful, controlled bass with excellent definition
Advanced active design with dedicated amps and power supplies per driver
Beautiful, high-end cabinet design and finish
Low noise and distortion; refined, non-fatiguing sound
Works well at both low and high listening levels
Reveals detail without overly punishing poorer recordings
Cons
Less airy/open presentation than some rivals
Large and heavy despite slim depth
Premium price
Requires high-quality partnering equipment to shine
Aesthetic and sound balance may not suit all tastes