Atoll ST300 Signature/AM300 Evo streaming pre & power amplifier
Having made Atoll’s IN400 Evo integrated amplifier a Product of the Year in 2025 I was very excited when two large boxes arrived containing the latest power amplifier and preamp/streamer from the same stable. I know that the AM300 Evo power amp will drive more or less anything thrown at it because I heard it effortlessly driving a pair of €99,000 Pen Audio speakers at a demonstration.
The ST300 Signature/AM300 Evo combo promise to be a step-up from any one-box solution, either the integrated or Atoll’s DSA200 and SDA300 all-in-ones that I liked so much. One special thing of note is that the ST300 has the added bonus of both Apple Airplay compatibility and Qobuz Connect, although I’ve previously raved about Atoll’s own app which has native Qobuz access.
The French factor
Atoll is one of those brands that deserves a higher profile; it produces a range of high-quality electronics that are all designed and manufactured in France. I am pleased to say that awareness of their excellence, in the UK at least, is growing. The company was founded in 1997 by Stephane and Emmanuel Dubreuil at Brécey, in Normandy. A year later products began to hit the high street while 2001 saw the company needing to move to larger premises.
Being the only French brand to have Dolby and DTS licences at the time, it’s little wonder that Atoll produced home-theatre products with a three-year research programme culminating in 2004 with its first multi-channel system. Extending their headquarters in 2016 to meet rising demand, Atoll has managed to keep both R&D and manufacturing in house which is very refreshing when so much production of audiophile electronics has moved to the Far East on cost grounds.
Streaming solution
In the Atoll ST300 Signature we have a network player that’s an improved version of the ST200. It was a long time in gestation, as most Atoll products are, since they are not launched until every aspect satisfies the demanding R&D team. Hence, we still await the mega SDA400 single box streaming amp; fingered are crossed for at least a pre-production unit at May’s High End show in Vienna.
Meanwhile, the ST300 Signature does everything one could want with the fascia featuring a five-inch TFT colour display, use of Atoll’s own easy-to-use app along with front panel controls and a supplied remote simply bristling with buttons. In fact, far too many for comfortable operation– many of them are for other components such as an Atoll CD player, so I eschewed the handset in favour of the easy-to-use app.
To the rear, the ST300 Signature sports excellent quality (gold-plated, Teflon-insulated) RCA connectors for a pair of analogue inputs and both fixed and variable level outputs, while a balanced out is also available and may be used simultaneously if required.
Digitally, the streamer boasts coax and optical S/PDIF inputs along with USB-As both back and front, Bluetooth, ethernet connection along with wi-fi for those who prefer. There is both coax and optical digital out for anyone who feels the onboard electronics are not sufficient. Although those comprise a Cirrus Logic CS8418 receiver supporting up to 192kHz and known for its very low jitter clock. Meanwhile digital-to-analogue conversion is courtesy of Texas Instruments/Burr Brown PCM1792 circuits, one per channel to reach a claimed S/N figure of 132dB. Not bad going. Carefully selected Clarity capacitors are deployed in crucial circuit areas.
While the ST300 Signature can handle a multitude of digital files (such as PCM, FLAC, ALAC, WAV, AAC and MP3) up to 24-bit, 192kHz, as well as DSD 64 and 128 formats, for me the convenience is the addition of Qobuz Connect and Apple Airplay alongside other platforms previously supported by Atoll, including Deezer, Tidal, Amazon and Spotify, not to mention Airable radio to access countless internet radio stations around the globe.
All this adds up to a finely crafted unit, solidly built with dual-mono construction, dual-mono DAC chips, pure Class-A resistor-array volume control (with no feedback), and enough I/Os to suit anyone. There’s even a mini headphone socket on the front panel, about the only thing missing is a USB-B input so that I can connect my laptop to run response tests on loudspeakers.
Powerhouse
An integrated streamer/network player like the ST300 Signature needs an amplifier. Atoll suggests partnering it with their AM300 Evo which can be used on its own, bridgeable to run as a monoblock or in an array for bi-amping in a mighty powerhouse configuration. I was sent a single unit and left it in stereo mode, connecting with XLR balanced leads. Its stats are impressive while the price is not exorbitant by any means, especially for a heavyweight unit that’s made in France.
The sturdy casework consists of 8mm brushed aluminium for the fascia while inside (in a dual-mono architecture) there are a pair of 440VA toroidal transformers, eight 6,800uF Atoll-specified capacitors, six MosFet output devices per channel working in a triple push-pull configuration to give 180W/ch in stereo rising to 500W in bridged mode (both into 8 ohms). Double-sided circuit boards are used, with nickel/gold finish, alongside polarization of the output stages which run in Class A/B. Input is either via balanced XLR or RCA phono connectors with stereo line out offered alongside two pairs of chunky binding posts for loudspeaker cables. All-in-all, an impressive piece of kit that’s solidly built.
One minor grip was that the power amp was not controlled by the remote or the app, but this can be resolved by using the 12V trigger connections which one would do in a permanent installation rather than for an ad hoc review period.
Listen up
When the amplifiers arrived, I was in the middle of assessing some Fyne F55s, modestly priced but proving to work rather well in a space where floor-standing transducers often struggle with the room acoustics. The Atoll electronics proved a delightful pairing for the F55Es and the system really sang. Proving that top-class amplification can really lift a loudspeaker’s performance. Budget speakers frequently appreciate a good amp.
From baroque, piano, full orchestra or oratorio through to pop vocals and heavy rock, the F55Es driven by the ST300 Signature/AM300 Evo took it all on and produced a lifelike sound of enormous weight and character that truly entertained. My only gripe was how the ST300 Signature would not remember its setting on power-up; I wanted it to start streaming the same source as when I had switched it off, but no. You have to reselect from scratch.
I also had to hand a pair of Tangent’s latest two-way stand-mounts from Denmark, the Spectrum X5s in Mark II guise. Sonically, the match with the Atoll electronics could not have been better. With the ST300 Signature making the world of internet radio available, BBC Radio 3 had a lunchtime recital featuring Shostakovich’s Piano Concerto Number Two with lots of lovely ambience from the venue coming across. It made me turn to the 1958 mono recording with the composer at the keyboard. There was plenty of detail in the reproduction of an instrument which can be an acid test for audio systems. We were treated to a natural sounding piano, as brisk and lively as I’ve ever heard it, with a lovely sparkle to the top-end while the midrange was clean and free from unwanted artefacts. Midrange clarity was confirmed during many hours of speech-based material in the panel’s absence, including TV soundtracks and radio drama, much which is very familiar to me. Voices sounded natural in a balance that was clear, clean and sweet if not quite as warm as my usual setup.
Vocals, also, were handled well by the Atoll ST300 Signature/AM300 Evo when driving the little Spectrums and, thankfully, they don’t have a forward presentation that places the performer in the listener’s lap which can be the ‘modern way’. With T’Pau’s 1987 pop/rock hit Heart and Soul the system handled the multi-layered production better than I had expected. Carol Decker’s powerful vocals were well balanced, in the right place and the right proportion. The track’s distinctive blend of spoken-word verses and its driving, high-energy chorus can be an unpleasant, muddled blur. Not here. We were treated to excellent reproduction of the atmospheric opening before the build-up into the fast-paced, synth-heavy rock anthem which lost very little thanks to the control provided by the Atoll ST300 Signature/AM300 Evo. Impressive stuff.
French & French
Next I placed my Revival Atalante 3 speakers centre stage to give a totally French-designed system. I don’t think there’s been a single Atoll product that I’ve reviewed and not truly admired for both its sound quality, build and affordability. It seems as though the ST300 Signature/AM300 Evo combination wasn’t going to disappoint and this was confirmed with the Revivals in their usual place. They showed off the Atoll electronics’ abilities as I was treated to levels of refinement above the norm.
Music had speed, agility, energy but also enormous detail and resolution such that I was convinced I was listening to studio amplifiers. Atoll products are at the top-end of hi-fi, verging into pro territory and create almost holographic, three-dimensional soundscapes by not only pinpointing the position of performers but allowing the listener to follow their every move. This is truly breathtaking. The electronics were not trying to stamp their own mark on the input material, but kept things natural and as the recording engineers intended; to me, accuracy is the pinnacle of precision amplification.
Euro coupling
Repacking the AM300 Evo for its return to Replay Audio, I decided to use the rather good ST300 Signature with my trusty Trigon Dwarf II monoblocks since I know how well they drive my Revival monitors and what the sound is like from other streamers and sources. Wow! This was an incredible Euro coupling with French front-end and German power into the Revival Atalante 3s. With the 2012 remix of Supertramp’s Live in Paris 1979, and an intention to listen only to the polished, high-energy performance of The Logical Song, we were so drawn in to the music that our feet also tapped along to Dreamer and the rest of the album as we wallowed in remarkable sound.
In the new pairing, the streamer/network player retained all of its former attributes but sounded more whole and complete in a way that is quite hard to describe. Needless to say, I’ve not heard my loudspeakers sound any better. And the same was true when switching to speech.
The smooth, refined, detailed, perfectly balanced sound with oodles of resolution was lifted with the Trigons, it wasn’t as smooth as with the Atoll combo, but the presentation was very much to my liking, and suited my Atalante 3 speakers perfectly. Imaging, timing and the sheer scale of the stereo landscape was awesome; not putting a foot wrong as far as I was concerned. Recordings of my own sounded as I remembered them when they left the studio and were free from blemish and unwanted artefacts such as sibilance or nasality which lesser electronics can impose.
There was a huge sense of the AM300 Signature’s dynamic ability, even on more demanding raucous material, with never a hint that the amplifier didn’t have plenty in reserve or might be in danger of running out of oomph. This noticeable especially on large-scale classical material which was notable for its dynamic range, I marvelled at the reproduction of Strauss’s Also sprach Zarathustra (Haitink/Concertgebouw from 1973 on Phillips) being so large and lifelike, bursting with orchestral excitement and bewitching luminosity.
Winning combo
Superb design, excellent build quality exuding a feeling of craftsmanship, and a combination simply bristling with features, the Atoll ST300 Signature/AM300 Evo is a winning combo if ever I have heard one. The engineers in Normandy have done a stunning job to improve the already excellent ST200 but in the upgraded model they’ve really packed a punch. I love the ease and simplicity of operation, the way music is to hand and, best of all, the sound quality.
I am almost embarrassed to admit that I’ve become so used to the all-in-one box solutions now flooding the audiophile market, including the mighty Hegel H600, that I’d forgotten how much can be achieved by removing the power stages and keeping them in their own box with separate power supplies. Anyone looking for a two-box streamer/amplifier solution should not hesitate in listening to what the Atoll ST300 Signature/AM300 Evo can do. You won’t be disappointed.
Pros
Exceptional power: The AM300 Evo is a ‘powerhouse’ capable of driving demanding speakers effortlessly.
Neutral & accurate: The Atoll pairing produced a ‘studio amplifier’ feel, offering high resolution and detail without stamping its own character on the music.
Holographic imaging: Excellent three-dimensional soundstage and pinpoint positioning of performers.
Dynamic range: Handles large-scale classical works and high-energy rock with massive reserves of ‘oomph.’
Refined midrange: Natural-sounding vocals and speech, free from unwanted artifacts like sibilance.
Versatile streaming: Includes Qobuz Connect, Apple Airplay, Tidal, Deezer, and Amazon Music.
Comprehensive connectivity: Features balanced XLR and RCA connections, multiple digital inputs (coax, optical, USB-A) and Bluetooth.
Dual-mono construction: High-quality internal architecture with dual DAC chips and independent power transformers in the AM300 Evo.
Bridgeable: The AM300 Evo can be bridged into a monoblock for even more power or used in a bi-amping configuration.
High-end build: Features 8mm brushed aluminium fascias, gold-plated connectors, and high-quality internal components (Clarity capacitors, Burr Brown DACs).
Made in France: Entirely designed and manufactured in-house in Normandy, France.
User-friendly app: The proprietary Atoll app is easy to use and superior to the physical remote.
Cons
Memory issues: The ST300 Signature does not remember its last setting on power-up; users must reselect their source from scratch every time it is turned on.
Overwhelming remote: The supplied handset is ‘bristling with buttons,’ many of which are for other Atoll components (like CD players), making it uncomfortable to use.
Lack of sync: The power amplifier is not automatically controlled by the app or the streamer’s remote unless the user sets up a 12V trigger cable.
No USB-B input: The reviewer noted the absence of a USB-B port, which prevents direct connection to a laptop for specific audio tests or playback.
Slightly soft balance: While clear and clean, the power amp’s balance was a bit softer and smoother than the reference monoblocks.