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Aesthetix Janus preamplifier and Atlas power amplifier

Aesthetix Janus preamplifier and Atlas power amplifier

The all-tube moving-coil stage is a rare beast indeed. Whilst tube phono-stages are both common-place and popular, when it comes to low-output moving-coil cartridges, the vast majority switch to either transformers (Zanden) or J-FETs (Audio Research) to achieve the additional, noise-free gain required. The one exception is – and seemingly always has been – Aesthetix, whose original Io all-tube phono-stage established the blue-print that the company has followed ever since. The original Io was big (running in its ultimate form to three large chassis), complex and expensive. It has evolved through several iterations to its current flagship form, the Io Eclipse, still a substantial three-chassis unit housing a total of 36 tubes. But it has also been joined by the Rhea: sleeker, more affordable and being built into just one-box, far more svelte. With a ‘mere’ 10 tubes, it’s a lot more affordable and only gives away 5dB of overall gain compared to its big brother. That means that you get variable gain of up to 75dB, remotely switchable loading, multiple inputs, a choice of balanced or single-ended outputs and a built in cartridge de-mag circuit, all in a neat and really rather stylish casing. But such elegant versatility inevitably costs. Throw in the matching Calypso line-stage and you are looking at the wrong side of £9,000, with the Signature versions featuring upgraded internal components adding a further £4,500. Not cheap, although considerably more affordable than the Io Eclipse and its partnering line-stage, a combination that can easily push way up beyond the £30K mark, depending on configuration.

Such prices demand performance to match and in that regard the Aesthetix units don’t disappoint, individually or in tandem: while the Rhea and Calypso turn in excellent results used in isolation, there’s no escaping the fact that used together, the whole is significantly greater than the sum of the parts – the two dovetailing to impressive musical effect. Which rather invites the question, ‘what happens if you combine the two in a single box’? Given that the casework and power supply collectively swallow a large share of the parts budget, doubling up could deliver real gains in terms of value, especially if you can do so without compromising the performance.

Enter the Janus, to all intents and purposes, just what I’ve outlined above. Built into its single slim-line housing you get a full-facilities preamplifier, including phono stage with variable gain from 40 to 75dB, adjustable loading and the de-mag circuit. You get the same 88-step volume control as used in the Calypso, phase inversion switch, feed-back free circuitry and balanced and single-ended options on all inputs and outputs (except phono). In fact, the only thing you lose is the two extra phono inputs featured on the Rhea. That and save a whole hunk of money! The sheer range of facilities and inputs makes both the front and back panels of the Janus pretty crowded but that’s a small price to pay. Besides which, the signature triangular buttons and window rocker volume/setting control that Aesthetix employ keeps things neat, clean and surprisingly spacious when it comes to operating the unit, while all functions are available via the basic but comprehensive remote control handset.


Take a look at the Aesthetix range and the natural partner for the Janus takes the imposing shape of the Atlas stereo amplifier. Large, seriously heavy (this thing has impacted my lower back on at least two separate occasions) and seriously capable, the Atlas is a tube driven hybrid design that will dump 200 Watts into an 8 Ohm load and 400 Watts in 4 Ohms. Despite employing the same basic chassis architecture as the Janus – albeit in outsized form – there’s no way an amplifier with this sort of muscle comes cheap and there’s no way I’d describe an £8.1K price tag in those terms: except that compared to most of the opposition it actually starts to look pretty reasonable. With the majority of stereo chassis amplifiers approaching this sort of output power fetching up well into five-figures, the Atlas really does look underpriced – and that’s before you’ve listened to it. Throw in balanced or single-ended connection, a massive power supply with two transformers and three chokes – one of each dedicated to the HT rail – and operational niceties like a front-panel mute and you’ve got a product that’s not just impressively capable, it’s actually easy to live with – just so long as you don’t need to move it about too often! Factor in the option to upgrade either unit to Signature status at a later date and you’ve got a pairing that’s not just versatile, but one that will embrace your system as it grows – and can grow with your ambitions too.

Now, remember what I said about the Rhea and Calypso used together? The same is true of the Janus and Atlas; things just keep getting better. Used alone, the Atlas is big, enthusiastic and dynamic, bringing an unstoppable sense of momentum to proceedings, the feeling that your speakers are being kindly coerced to perform within an inch of their lives. With this much power on tap, you certainly could take things too far, but I doubt your ears (or your nerve) would let you. The Atlas simply sounds so boundlessly powerful that the need to prove the point (or stretch the envelope) never really seems to occur. Such obvious power serves as its own warning – a bit like a live wire quivering with voltage in a sci-fi movie. In contrast, the Janus is a model of restraint, big on the traditional tube virtues of colour, shape and musical flow. It is a model of refined grace and expressively quick but unexaggerated dynamics. But combine the two and they build on each other’s virtues – the Atlas gains a measure of polish and poise, the Janus an injection of sheer presence and immediacy. Together the combination has the sort of fluid, feline grace and explosive power that makes big cats so fascinating. Ask the Aesthetix amps to jump and the question really is, “How high?” – it’s just that it’s your speakers that will be asking. Gone is any lack of control, replaced by complete security and the sort of authority that escapes most audio systems. As attractive as the virtues of these two Aesthetix pieces are in isolation, put them together and suddenly it really is time to play…

If you want to know just what these amps are capable of then start by hooking them up to a speaker with decent bandwidth and a desire to be dominated. That means all those speakers that are hard to drive, have weird impedance curves or simply fail to spark into life, no matter what you do to them under normal circumstances. As good as the results you might have heard from those products in the past, prepare to be surprised: speakers that so often fail to really integrate, to drive the room or respond to dynamic demands will suddenly come over all obedient and enthusiastic. Of course, it’s not the speakers that have changed, it’s just one symptom of the degree of control that these Aesthetix amps can exert and just how impervious to back EMF the Atlas output stage is. But it’s not just about control; there are plenty of amps that exert an iron grip – and crush the life out of music in the process. What makes the Janus and Atlas so special is the fact that they do control AND life, definition AND dynamics, authority AND entertainment.


Large-scale works are produced with substance and stability, a stability that extends beyond the clearly defined soundstage into the realm of rhythm and timing. Shawn Colvin’s Steady On (CBS 466142-1) features a trip-hammer drum-beat that both anchors and drives every track, but you’ll rarely have heard it projected as solidly or with such impetus as the Aesthetix achieve. The propulsive effect is remarkable, underpinning and pushing the vocal forward. And what a vocal; Colvin’s voice is deceptively sweet given the acid content of the lyrics, the Aesthetix combination revealing both the pain and the anger behind the words. This is a real voice from a real person singing about real events and the amps leave you in no doubt about that. I ran the amps with both my vdH Condor and the Goldfinger Statement, the Janus offering more than enough gain for either, with no noise problems. In fact, the 6dB stepped gain options allow you to balance musical energy against noise in a way that fixed gain stages can’t match. The result is LP reproduction with clarity and resolution, substance and power, a sense of flow and forward motion, natural colours and a complete absence of that synthetic edge or etching that marks out hi-fi from music. It’s a character that offers the perfect foundation for the substantial reinforcement provided by the Atlas, a character that carries over to the reproduction of silver disc. Ryan Adams’ Heartbreaker is full of presence and body, subtlety and deft rhythmic touches, while the deep bass incursions that underpin a track like ‘AMY’ are still solid, still come as a surprise. It’s this ability to be solid and stable without becoming planted or static that brings the intimacy and directness to the music played on the Aesthetix pairing. Whilst you’d never mistake this for a small amp, it embodies so many small amp attributes (rhythmic flexibility, natural dynamic expression and warmth, immediacy and communication) that the presence of not just big amp virtues, but big amp virtues done really well can come as a shock. The unmistakable backing vocals from Emmylou Harris on ‘Oh My Sweet Carolina’ are almost ghostly real, while the building chorus and almost anthemic finale swell from nothing, leaving you wondering just where they came from. Turn to big-time classical and orchestral sweep can almost literally sweep you away.

Like every other piece of audio equipment, the Aesthetix Janus and Atlas will always be prey to context. Put them with the wrong partners and they’ll sound sluggish and heavy, dull and overbearing. But unlike most amplifiers, the thing to avoid here is speakers that don’t need (or want) what these amps have to offer. Easy to drive with a tailored bottom-end? Look elsewhere. Super sensitive and high impedance? Definitely look elsewhere. Just don’t be fooled by the numbers. On paper, the Focal Scala V2 – at 92dB sensitivity and a nominal 8 Ohm load – look like exactly the sort of speaker the Aesthetix should avoid, but dig a little deeper and you’ll notice that not only does the impedance curve exhibit a 3.1 Ohm minimum, but the -3dB point at 27Hz is generated from a single 270mm woofer in a true three-way configuration. That’s definitely the sort of speaker that will really benefit from the light-touch control and load tolerance available from the Aesthetix amps, while their sheer class will also make the most of the amps’ refinement. No surprise then that the combination is a spectacularly successful one, reflected by the fact that the Scala V2s, driven by the Atlas mono-blocs and Io/Calypso Eclipse offered one of the best sounds at RMAF 2013 – easily outpacing the vastly more expensive Stella/Soulution system that was also on show! Get it right and these amps will really reward you, their positive attitude bearing magical musical fruit.

Big, bold, solid and surprisingly agile, these amps are good enough and communicative enough to put you really close to the performers and their performance. With unforced power and a real sense of presence, they project music with an uncannily natural sense of pace, flow and colour. Having run the Atlas in a few systems now, it has become a real go-to amp. The Janus, despite the astonishing value, will clearly only appeal to those who use, or want to get back into using, vinyl. For everybody else, there’s always the Calypso – at £4,850. That makes the phono-stage in the Janus pretty much a £1,950 option and at that price it will come as little short of a revelation to many listeners – especially those used to the one size fits all approach adopted by so (too?) many manufacturers. It’s not until you use these Aesthetix electronics together that you realize their full potential – and believe me, that potential is considerable!

Technical Specifications

Aesthetix Janus

Tube Complement: 8x 12AX7, 4x 6922/6DJ8

Inputs: 5x line-level (balanced or single-ended)
1x phono mm/mc (40 – 75dB gain)

Cartridge Loading: 9 values from 75 Ohms to 47 kOhms

Line-level Gain: 23dB

Cartridge De-mag: Yes

Absolute Phase: Yes

Outputs: 2 pairs XLR, 2 pairs RCA

Output Impedance: 1 kOhm single-ended,
600 Ohms balanced

Dimensions (HxWxD): 120 x 455 x 458mm

Weight: 18.2kg

Price: £6,800

Aesthetix Atlas

Tube Complement: 2x 6SN7

Rated Output: 200 Watts/8 Ohms; 400 Watts/4 Ohms

Input Impedance: 470 kOhms

Input Sensitivity: 60mV (1 Watt), 2.3V (full power)

Dimensions (WxHxD): 458 x 203 x 483mm

Weight: 32kg (claimed – but my back says they’re lying!)

Price: £8,100

Manufactured by Aesthetix

URL: www.aesthetix.net

Authorised UK stockists:

Cool Gales: +44(0)800 043 6710

Hi-Fi Sound: +44(0)845 601 9390

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