ATC has an enviable reputation in the pro audio world for its active monitors. These are often substantial speakers that combine classic but refined technologies to produce highly revealing and neutral results. The sort of results that professionals are happy to rely on. What is less obvious is the remarkable value the company appears to offer given its size. It may be Stroud’s finest manufacturer of audio equipment but it’s a small business in the general scheme of things. Yet it manages to produce a 150 watt pre/power combo for just over two and a half grand, what–you might ask–gives?
Having probed this point for some time it would seem that it’s a case of keeping margins down across the board. ATC doesn’t make a lot from each sale and nor do its dealers, which is why you don’t see its kit as often as you should. But fortunately there are still some retailers who are into it for more than the money, people who are willing to forego a bit of profit in order to provide great value to their customers. An approach that hopefully nets them loyalty, which is something that ATC seems to have in the pro world. We are told that the company is so busy with custom jobs for studios and concert halls that it isn’t too concerned about how well or otherwise its equipment does in the hi-fi world. However, this doesn’t tally with products like the pre/power combo here. After all, ATC already makes a preamp and power amp called SCA2/SPA2-150, there’s even an integrated (SIA2-150) so why bother making a more affordable one, a much more affordable one at that? The CA2/P1 cost about the same as an SIA2-150 and has the same power; in fact, all the ATC amplifiers are 150 watt designs built to the same design, but with greater refinement through higher quality parts etc in the top model. That probably helps keep the price down as well.
The CA2 is a very nicely executed preamplifier, with a solid 12.7mm thick brushed aluminium fascia. This is inlaid with black bars either side and held on with four discreet fixings that look like buttons. In fact, only the two inner domes are buttons, for power and tape monitor, the rotary knobs, also domed, control volume and input selection. The latter takes a bit of getting used to as it moves the LED across the various inputs named in the centre rather than pointing to inputs around its perimeter, but even I was able to master this peccadillo.
What foxed me however is the way that the phono input is named on the back panel. As it’s an either/or input that can be configured for line or phono sources the script by the sockets and on the front panel reads ‘Aux 2’. You’d probably be told whether it had a phono stage onboard if you bought it or you might even read the manual. But as I didn’t have the latter, somewhat inevitably I chose this input to connect a CD player to and this may be why the phono stage failed to work as desired when I finally got around to trying it with a turntable?
You can change it from an MM to an MC stage internally, but figuring out how to do so proved a little tricky as the labelling on the board is pretty obtuse and the instructions not significantly clearer. However, a little trial and error produced a result that worked with my van den Hul Condor moving coil. You can adjust sensitivity for cartridges with between 0.7mV and 10mV output with five increments in between and choose either 100 ohms or 47k ohms impedance. This is the degree of flexibility you get with a good phono stage, but it’s pretty rare in a preamplifier.
Input socketry is all single ended RCA phono, but there is an XLR output alongside the phonos as well as outputs for a subwoofer and tape. It has a headphone output on the back should you need to do a bit of discreet listening. Inside the box is a low noise circuit with fully regulated power supplies for each channel, ATC avoids ICs in the signal path because it feels they can distort phase and uses discrete gain blocks to provide amplification. Bandwidth is quoted as DC to greater than 200kHz and THD as bettering 110dB, the SCA2 at about four times the price gives you another 300k bandwidth and four extra decibels of ‘quiet’ between signal and noise. It is however fully balanced which is useful. Control can be achieved with a rather unglamorous but totally practical remote handset which also provides basic controls for a CD player using the popular Philips RC5 protocol.
The P1 power amplifier has matching metalwork to the CA2, but I wouldn’t suggest you stack the pre on top of the power for obvious thermal reasons. It weighs in at a respectable 23kg (50lbs) thanks to a 300 VA transformer for each channel. This is a true dual mono, class A/B power amp, which lives up to its output rating if independent tests are to be believed. Power is delivered by two pairs of MOSFETs per channel through a single pair of small but strong speaker terminals that will accept spade or banana connectors, or even bare wire if you feel the urge. Input socketry is in both flavours and there are link connections for each channel that can pass the signal onto another power amp. Unusually for a power amp, it can be powered up/down with the remote but the option exists to defeat this mode.
I started out by substituting the P1 for a Gamut D200 MkIII in a system with Bowers & Wilkins 802D speakers doing the transducing, and this revealed a matter of fact, no pussy footing character that is definite about what’s going on. It is also very solid and grounded so there is plenty of control and weight in the bottom end which provides a firm anchor with which to tether the soundstage in the room. You can hear the not insubstantial drop in price between the Gamut and the ATC, but the latter does little that gets in the way of the music. In fact, the quality of timing is so good that the musical flow is totally unhampered, free to go where it wants to with a strong sense of purpose.
In detail terms, the P1 is as refined as you’d expect at the price. It’s not unduly revealing, but neither does it veil details that are important when it comes to understanding how recordings have been put together. Despite having a slightly lower power rating than the Gamut, it has stronger bass. This underpins records like Antonio Forcione’s Tears of Joy to great effect, revealing more about the space he’s playing in than other amps if not elaborating on the more romantic aspects of his playing. The mid for instance is a little short on sparkle, but the overall result is very strong on musical engagement and that should be a fundamental goal for any audio component.
Using the CA2 preamp with a pair of ATC SCM150ASL Pro active speakers in place of an Audiozone Pre-1 TVC the result is once again strong on power. Kick drums have real energy and become more lifelike and visceral. Likewise, all electric instruments are far more real. It’s a bit of an apples and pears comparison though, the passive controller is cleaner but lacks dynamics which makes the powered nature of the CA2 more apparent. It in turn sounds distinctly electric by comparison, but does a rather better job at delivering the power of the music. In short, you either like Marmite or you don’t! I prefer listening to music. More useful perhaps is comparing the CA2 with another active preamp namely the Class? CP-700, once again the result was a notable increase in bass weight alongside a tighter, snappier presentation that gives the music far more get up and go. The flipside of this is that it’s less relaxed and there is a shortfall in fine detail of the sort that reveals the tonal shading of each note and the decay that goes with it. But remember that the Class? is also a rather more expensive beast and I would happily trade some of its finesse for a bit more zip.
Using both CA2 and P1 together through the 802Ds provided a full scale, full power experience that brings dynamic recordings to life. Muddy Waters’ Folk Singer is a high energy recording with some occasionally savage mic abuse, the ATCs let it deliver all of its energy thanks to the ability that these amps have to unleash controlled power just when it’s needed. Keith Jarrett’s Carnegie Hall performance is not short of meat on the bone either, the tempo is strong and the piano bodacious. This pairing concentrates on the fundamentals and gets them spot on, so the timing is locked down and the headroom allows the instrument’s dynamics to ebb and flow in realistic fashion.
There are lower powered amplifiers that can deliver more of the harmonics and tonal richness from a recording but they don’t usually back it up with the dynamics on offer here. At this price point there are always compromises to be made and ATC has focused on making an amplifier that delivers the core elements of the music in realistic and timely fashion. Leema’s Tucana II (?3,425) Integrated for instance has a more open midband in the context of a relaxed and revealing presentation, albeit one that can’t compete with the P1’s sheer grunt. Arcam’s A38 (?1,450) on the other hand is a bit more frenetic than the ATC pairing, which produced a more fleshed out sound that is itself relatively relaxed. I didn’t have anything more closely matched price wise but you can see that the ATCs fit into the scheme of things in terms of detail but rise above their station when it comes to power and timing.
ATC kindly supplied a second CA2 with a fully intact phono stage which gave me the opportunity to put this particular input through its paces. With an MM cartridge it did the same trick as the rest of the amplifier by beefing up the bottom end and this gives the sound a greater sense of solidity overall. More significant however is the way it can pull realistic sound out of a modest turntable, I had a Rega RP1 in for review and this sounded pretty crisp and timely with a Trichord Dino phono stage but going directly into the phono stage resulted in the nature of percussion instruments being made more clear at the cost of a reduction in zing from the acoustic steel string. The outboard stage was inevitably combined with an interconnect which is an extra barrier but this was nonetheless a good result for the preamp. Impressively it even worked well with a low output MC (van den Hul Colibri), in my experience few onboard MC stages to cope with such things very well.
This pairing doesn’t have some of the features that the competition is beginning to add such as digital and USB inputs, instead what it gives you is solid engineering and build quality for the money. The sound is reminiscent of pro audio, it delivers the fundamentals in a remarkably coherent and down to earth way. If you are looking for cavernous soundstages or inky black backgrounds you will have to pay rather more for it, but if you want to hear the important musical detail presented in a coherent, clear-cut fashion this pairing has remarkably little competition in the two box arena. There are a few integrateds around which give them a run for their money in one respect or another but nothing comes to mind which seems like a better overall package.
SPECS & PRICING
Input sensitivity 300mV
Input impedance 12 kohms
Dimensions (HxWxD) 90x445x330mm
6 year warranty
Rated power 150 watts per channel into 8 ohms
Input sensitivity 2V
Input impedance 10 kohms/leg
Dimensions (HxWxD) 135 x 435 x 350mm
6 year warranty
ATC Loudspeaker Technology Ltd,
Gypsy Lane, Aston Down, Stroud, Glos GL6 8HR
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