EQUIPMENT REVIEWSOULNOTE A-2
integrated amplifier
Jimmy HughesFounded in 2004 by ex Marantz engineer/
director Norinaga Nakazawa, SOULNOTE isa Japanese brand making high-end audioelectronics. The range includes amplifiers,DACs, an SACD player, and phono stages –all manufactured in Japan.
SOULNOTE divides its products into threetiers with 1 being ‘entry level’ (a relative term!) and 3 theirflagship series. All three levels feature outstanding buildquality and exemplary finish. The A-2 integrated amplifierforms part of the intermediate series 2 range.
It’s a fully-balanced dual-mono design using discrete
components throughout. Six line inputs are featured –three balanced (XLR) and three unbalanced (RCA). Power
output is 100W into 8 Ohms (200W into 4 Ohms) and theoutput stage operates in Class A/B. A large 600VA toroidaltransformer is employed. When idling, the amp draws
125W, rising to 355W at full power.
The power amp offers BTL (Bridge Tied Load) operation,and the amplifier can be used in one of six ways. With justthe one A-2, it can be used as an integrated amplifier or

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stereo power amplifier. However, add a second A-2 andthere are options to use it as either a pure dual-mono
integrated amplifier, a two-box dual-mono integrated
amp for bi-amplification, a bridged mono power amplifier
set-up or dual mono bi-amplifiers. The only pathways notopen to the listener are to use your collection of A-2s aspreamplifiers.
The output stage seems quite heavily biased towards
Class A so the amp runs a bit hotter than other similarClass A/B amps. Case temperature reaches about 44°C(110°F), which is fairly-warm, but not excessive. Weight is areassuring 20kg and build-quality is excellent.

No negative feedback
Zero negative feedback is a crucial part of SOULNOTE’s
design philosophy. Chief designer Hideki Kato assertsthat NFB produces no benefit in terms of sound quality.
Measured steady-state specs might show improvement,
but music is dynamic rather than static.
It’s akin to testing a car by driving it at speed on a flatstraight road. It tells you how fast the vehicle can go, but

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EQUIPMENT REVIEWSOULNOTE A-2

Kato-san believes superior sound quality depends on accurate
reproduction of the original waveform in the time domain.

doesn’t indicate manoeuvrability, or how well it accelerates
or de-accelerates. Music is a bumpy road full of twists andturns, hills and dales, starts and stops...
Kato-san believes superior sound quality depends
on accurate reproduction of the original waveform in thetime domain. Unfortunately this is difficult to measure;changes for the better do not always produce measureable
improvements.
Consequently, SOULNOTE insists on listening tests tooptimise things like circuit design, board layout, component
choice, and mechanical construction. Make the right calls inthese areas and you should start to get somewhere...
Ironically, the A-2 produces excellent static
measurements. Distortion is very low at 0.03%, and thebandwidth of the amplifier runs from a subterranean 3Hz all
the way to 240kHz. SOULNOTE avoids DC servo circuits
and current-mirror circuits due to their adverse effects onsound quality.
Volume is controlled by a balanced attenuator switch
using high-quality relays and precision fixed-resistors, rather
than a conventional potentiometer or an electronic system.
SOULNOTE claims this dramatically increases clarity,
creating a more three dimensional sound image.
The use of fixed resistors also improves left/rightchannel-balance accuracy at low volume levels. However,a downside of this arrangement is it limits the number of
discrete level steps to just 35 in 2dB increments. So, ultrafine adjustment of volume level is compromised slightly.
Is this a big drawback? Well, at times I’d have liked toset volume at a point in-between the options offered by
the A-2. But if the use of fixed resistors and relay switchingoffers improved sound quality over standard volume-control
methods, it’s definitely worth having...

Reproduced from hi-fi+ Issue 215Look Ma, no DAC
Somewhat unusually for a modern amp, the A-2 does notcontain a DAC. Maybe that’s a nod to the old Marantz
philosophy of always keeping analogue and digital inseparate boxes. But there’s a more practical reason withSOULNOTE – lack of space.
The use of discrete components in the A-2 means theamplifier’s innards are pretty-full. There simply isn’t room fora DAC – especially not one using discrete components like
SOULNOTE’s D-2. A peek inside the latter will soon makethis clear...
Electronically, the A-2 is more or less silent. Even using
102dB sensitive Klipsch Cornwall IVs, there’s no residual
hiss or hum discernable. However, there is a small degreeof mechanical transformer buzz that’s just detectible when
you’re very close to the unit – but is otherwise inaudible.
The amplifier sits on three flat metal feet which can befitted with spikes (supplied) if desired. The aluminium top
plate is loose and decoupled, rather than screwed-downtight; most unusual. Front and Side panels are 1.5cm thickaluminium, and ribbed for added strength.
First impressions were of a clean solidly-focused sound –muscular, detailed, and clear, yet often surprisingly delicate
and expressive. Musically, the SOULNOTE A-2 delivered
authoritative results, yet sounded flexible and fluid. It was
tight and defined without sounding rigid or over-controlled.
The A-2 let you hear deep into the mix. It was able toreveal subtle detail in the music; the specific qualities andcharacteristics of different recordings could be discernedvery clearly. It seemed to tease-out more individuality,
more variation.
Comparing the A-2 to my Musical Fidelity Nu-Vista 800,
the MF was a tad drier and more-forward; it sounded

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EQUIPMENT REVIEWSOULNOTE A-2

The A-2 kept the notes separate, conveying something thatrhythmically felt more distinctive and expressive.

‘flatter’ with less spatial depth. The SOULNOTE had agreater sense of space and refinement, with increasedimmediacy and clarity – qualities that made for a truer
more-realistic sound.
On The Best of Lee Ritenour the sound was very
holographic, with excellent ‘out of the box’ imaging andvivid stereo with a nice sense of depth perspective. Tracks
like ‘Sun Song’, ‘Captain Fingers’, and ‘Caterpillar’ soundedsmooth and refined, yet crisp and immediate – full of impact
and attack.
Playing an Opus 3 CD of Knud Jorgensen’s Jazz trio on[CD 8401] Jorgensen’s piano sounded brilliant with a nicebright tactile tone. At 5m 38s, he plays a brief arpeggio –albeit, it more like a fast sweep chord than a true arpeggiowith distinct individual notes.
The A-2 kept the notes separate, conveying somethingthat rhythmically felt more distinctive and expressive.
All those little pianistic ebbs and flows, stresses andhesitations, were faithfully conveyed by the A-2, making theplaying sound more expressive and interesting.
On Bach’s St John Passion with the Dunedin Consort
under John Butt [Linn SACD CDK 419] the voices soundednatural yet vivid and always very ‘present’. The end-result
was nicely-forward, without unwanted tonal hardness
or edge. The A-2 encompassed dynamic extremes
without strain.
Playing Snow Patrol’s album Eyes Open, the A-2
delivered strong full-blooded results that were clean andfree from congestion, even in the densest passages.
The vocals separated-out nicely, creating an enjoyabletransparent dimensional result that was clear, open,
and detailed.
The A-2 certainly sounded good, but didn’t impose
its own specific qualities or characteristics on the music.
Rather, it allowed the individual virtues of each recording
to shine through. The A-2 can be quite revealing of thingsother amps gloss-over, yet it’s not unforgiving.
On the Hyperion recording of Mozart’s piano concertos
11, 12, and 13 (chamber music versions) with Susan Tomesand the Gaudier Ensemble, the A-2 conveyed the delicate
intimacy created by the use of reduced forces, sounding
crisply-focused and effortlessly detailed.
Bass is firm, tight, and extended. The midband is solidand full, while the top sounds lucid and tactile. The overall
presentation is enticingly-smooth refined and fluid – albeit,
only if the original recording has these qualities. The A-2
doesn’t deliver a rose-tinted view of things.

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Fairy Dust excluded
It’s not an amplifier that sprinkles fairy-dust over recordings.
Yet while it’s certainly truthful, it’s not unkind, or intolerant offlaws. Although my review A-2 had seen action, the sounddefinitely eased-up and grew increasingly-sweeter andricher after four or five days’ steady use.
Using an external phono stage, the A-2 was great onvinyl. If CDs and Streaming were sometimes a bit too
precise – too sharp – LPs sounded crisp and focused yetspacious and not so tightly defined. Focus and Precisionwere evident, albeit with a more-friendly relaxed feel.
Once run-in, the A-2 sounds almost velvety – delivering a
flowing beguiling-mellifluousness allied to impressive clarityand definition. It sounds fast, smooth, sweet, and open, andhas the ability to highlight subtle differences in tonal balance
while revealing delicate micro-dynamics.
Yet there’s no lack of attack and immediacy when this iscalled for – a real iron fist in a velvet glove. It’s also capableof sounding very different from one album to the nextand even sometimes from track to track. The A-2 often
surprised me. I liked it the more I listened to it.
Built to high standards, SOULNOTE’s A-2 is an elegant
graceful amplifier with some impressive chops. It has thecrisp effortless authority and tonal refinement expected ofa good tube amplifier, and acts like an open window on
the music.

Technical specifications
Type Solid-state integrated amplifier with Bridged Tied Loaddual mono/bi-amp modes
Inputs 3× single-ended RCA pairs, 3x balanced XLR pairs.
Line-inputs only, optional use as mono inputs in BTL mode
Power Output 100W × 2(8Ω), 200W × 2(4Ω), 400W(BTLMONO 8Ω)
THD 0.03% (50W 8Ω)
Freq Response Speaker (8Ω 1W) 3Hz~240kHz( 1.0dB)
Impedance LINE 1,2,3,(Balance) 700mV/16kΩ,, LINE 4,5,6700mV/8kΩ
S/N 110dB (HF A Network)
Power Consumption 355W(J60065), 125W(Idling)
Measurement (W×H×D, with spikes) 43 × 16 × 41cm
Weight 20.0kgs
Price £6,300Manufacturer SOULNOTE
Distributor Kog Audio

www.soulnote.audio

www.kogaudio.com

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