Atoll SDA300 Signature streaming amplifier
Having thoroughly enjoyed the French Atoll SDA200 Signature streaming amp, and making it one of my 2022 Products of the Year, I was excited to hear the newly-launched SDA300 Signature at the Warsaw high-end show. My patience was rewarded when a unit, in very smart matt-black milled aluminium, arrived for review and evaluation in my own system. As a daily user of a streaming integrated from another marque I am well aware of the concept and the convenience that an all-in-one unit in this price-range offers. But how would this higher-powered Atoll unit sound?
Atoll Electronique
Atoll Electronique was founded in September 1997 by Stéphane and Emmanuel Dubreuil who felt that they could produce audiophile products at affordable prices. Based at Brecey, in Normandy, by the end of 1999 they had a range of three-channel amplifiers aim at home theatre customers. The company soon outgrew its initial facilities and moved into new premises in 2001 just as it launched its TU80 tuner and the start of a three-year project to create an AV preamp and maximise the fact that Atoll was then the only company in France to hold Dolby and DTS licences.
Having established a presence in the market, in 2005 Atoll decided to cater for more high-end requirements and a year later saw the launch of an audiophile range including a CD player. Further R&D led to a CD-SACD player and DVD machine. Entry-level products were next on the agenda and arrived in 2008 with a DAC the following year. With business growing, the top-end of the audio market was greeted by Atoll’s 400 range in 2010 followed by network players two years later and the first all-in-one unit in 2014.
All models are fully-assembled, tested and finalized in Atoll’s workshops to ensure reliability and complete control of the manufacturing process. The circuit boards are wired by hand, checked and measured individually before assembly. Finally, a complete test is carried out on each product before packaging and shipping. Such attention to detail and final QC is becoming too rare.
Design and features
The SDA300 Signature is certainly packed with features. About the only thing it doesn’t cater for is Apple Airplay (at least, not at present). The 19kg unit is bristling with connections, both in- and outputs, digital and analogue with twin RCA inputs alongside a pair of coaxial and two optical Toslink. There are also speaker outputs plus a pre-out, coax and optical S/PDIF outputs, with ethernet and power connections completing the back panel alongside Bluetooth and wifi antennas. The front is dominated by an 5-inch TFT display (without touch control) and a large, rotary/push control on either side, along with a headphone socket.
One feature I note in particular, since it’s missing from my daily amp, is the amazing ability to browse thousands of internet radio station, thanks to the inclusion of the Airable network. Here the dedicated Atoll App, now in Mk II form and greatly improved over the original, comes into its own for armchair browsing of worldwide sources. For those who prefer, a comprehensive remote handset is included and caters for everyday functionality.
There’s the option to stream in high definition from the likes of Qobuz, Tidal, Deezer, Spotify, Highresaudio, as well as twin USB connections (one front, one rear) for a NAS or thumb drive. All manner of files can be read in resolutions up to 24-bit/192kHz and DSD128. Everything appears to have been carefully thought through to cater for every user’s needs. The pre-out means the unit can be used as a pre-amp or connected to a pair of active subs for those who feel the desire.
The various inputs can be renamed by the user and those not used may be bypassed to reduce options when selecting a source. A nice touch. The DAC relies on the tried and tested Burr Brown PCM1792, and the amplifier is based around MOSFETs in a double push-pull configuration output stage to give 150W/ch into 8 Ohms, while careful thought has been given to component selection.
The SDA300 Signature in use
A product as sophisticated, complex even, as this deserves a few lines on its ease of operation. I noted how relatively cool it was in use, despite having Class-A circuitry. Atoll’s Stéphane Dubreuil explains that this is a design feature which has been given special attention by “using a direct coupling to the heatsinks which reduces thermal resistance; and developing a thermal regulation system to keep the heat output as stable as possible.”
Some audiophiles may be concerned to see both Bluetooth and wifi on such a product, fearing that provision will affect the sound quality. But, have no such fears, says Stéphane. “When you have ethernet connected the wifi is not active. It can be useful, in some cases, to have wifi possibility even if it’s not the type of connexion we recommend.” I agree; it’s an added bonus and will prove useful when a wired connection to the network cannot be made.
We talk about the lack of Apple Airplay, my preferred streaming method not least because I have hundreds of my personal recordings stored in Cloud. There could be marvellous news on the horizon, I learn. “We are working now on the possibility to add Airplay to our devices via a software update. The development process has started and we hope this will be possible before the end of 2024,” the designer tells me.
Sound quality
Connection to my local network (via ethernet), digital sources including a DVD player and satellite receiver, plus Tidal, Spotify and Qobuz accounts was all very straightforward. The Atoll arrived just in time because I was struggling with a lowish-impedance Audio Physic’s Classic 8 loudspeaker which my usual amp was struggling to drive. By contrast the SDA300 put up a commanding performance, helped by the unit’s 280W power output with 4 Ohm loads.
The Atoll delivered tight, precise and full-bodied bass. Indeed, there is an immense sense of control and tightness across the frequency range such that even the largest of crescendos remained dynamic and forceful with a warm, musical coherence. This was evident on the mighty forces of Mahler’s Second (CBSO/Rattle) where an acknowledged inflected interpretation of the work was reproduced with immense realism and forceful gravitas. The whole was enjoyed by the panel which rated the performance highly and noted that there was strength and detail to the sound which allowed engagement with the music, even from the first few notes.
The ability to play both softly as well as to cope with the power of this work was notable and we all agreed that articulation was superb, helped by the bass which was delivered with superb dynamics, even at modest listening levels. I had a feeling my neighbours would agree since I was conscious of not only my internal organs but also the floor vibrating.
By contrast, Vivaldi’s Gloria (King’s Cambridge/Cleobury) was a delight when streamed via the Atoll and, after the panel left, I played it again such was the level of clarity and listener involvement from this piece. The amplifier made the most of the refreshing lightness of texture which was brought home so vividly, the soloists so clear and uncoloured; the pensive cello causing me to tingle with excitement. The SDA300 Signature managed to reveal an incredible level of midrange and treble detail, to a degree not expected from an amplifier/speaker pairing at this price.
Moving to the 1986 Falco song Rock Me Amadeus (American Edit); the system took it all in its stride, re-creating the singer right there, in front of us, in flesh and blood as it were. The realism portrayed via the SDA300 Signature was uncanny; the reproduction precise as every guttural noise, every syllable came across loud and clear. The Atoll design gives the bass so much power; it is fast and pleasantly neutral. The pairing with the Audio Physic speaker imparted pinpoint imaging across an immense soundstage to draw the listener in very convincingly. The midrange reproduction was also refreshingly clean and uncoloured, never shrill or unpleasant as can be experienced from lesser designs.
The ability to engage the listener was reinforced with a track I’ve been using a lot lately, George Ezra’s Shotgun. Here we heard a huge amount of detail, our feet were soon tapping to the catchy, almost addictive tune and showing that the SDA300 Signature can do timing which means the tune whips along at pace as intended. I noted the natural midrange while others mentioned the tight, deep beats.
Switching to my Revival Audio Atalante 3 speakers, and we had French loudspeakers powered by French electronics. Coldplay’s Paradise popped up as a suggestion from my streaming service when I asked it what I should be listening to. It is an eclectic mix of boiling strings, rattling synthesizers, and bass-heavy-beats which were handled very well by the Atoll electronics such that I lapped up this slice of hug-warm ecstasy with extra toe-tapping enjoyment. The level of definition and detail is incredible and one could easily be forgiven for thinking the sound came from a system at many times the cost.
Rounding off critical listening sessions with Chris Dr Burgh’s The Crusader where the dynamic range in this track from his early years was incredibly well reproduced. We have what’s akin to a mini opera contained within an album track and the all-French system set-up was really on-song. The amplifier helps to deliver a very realistic soundstage with great imaging to draw the listener into the performance. The instruments are deliciously warm and inviting, the voice having a delightfully alluring presence. This Burr-Brown DAC has always been a favourite of mine for its overall softness of delivery even though many designers seem to have moved away from its once ubiquitous use.
For several weeks longer I kept the SDA300 Signature as the heart of my daily system and explored the thousands of internet radio stations, broadcasting from around the globe, in quiet moments between my usual diet of current affairs, drama and classical concerts. Throughout, the Atoll SDA300 Signature offers ease-of-use and an attractive warmth to the sound which makes me want to continue listening: that is the hallmark of not just a good amplifier, but a superb one.
Conclusion
As soon as Atoll confirms that the SDA300 Signature is Airplay-equipped I shall be placing my order to use this as a reference product. I like its styling, its ease of use and, best of all, its sound quality. The price is also competitive; there’s a lot for the money and it would cost considerably more to purchase separately the component parts from the Atoll range or any other reputable brand.
Overall, we have here a superbly engineered, well built (in France) streaming amplifier which sets a benchmark. Sound-wise it never fails to impress, with all manner of inputs sources and across many genres. The timing is spot-on, the soundstage wider and deeper than I recall from the SDA200, definition superb and both the dynamic abilities and detail extraction ahead of what one might expect at this price. Listeners are drawn into the music which become heavily engaging; so much so that it’s hard, very hard, to fault the sonics at all.