Review in “image-hifi” magazine (Germany), Issue 05/2012

Accuphase Preamplifier C-2820 & Power Amplifier P-6100

The Investment in Gold….
by Helmut Hack….may not be a good idea these days. The same applies to shares with all theirunclear risks. Is there at all any type of investment that can be considered asafe one? Excepting Accuphase, of course.
I don’t want to sound elitist, but still: the moment the masses out there are
jumping onto something or John Smith is going to rob his piggy bank in order totransfer the savings for blocks of shares or gold bars, you can be sure he’ll be taken
to the cleaners and most likely going to lose a large part of his savings. If youremember, this was the case a decade ago when Telekom shares were sold totrustful citizens who were evidently not aware of the fact that this state-owned
enterprise already belonged to them, as tax payers, so to speak. […] But things are
actually not so complicated in a free-market economy: prices go up with increasing
demand and inevitably will fall again in a saturated market. […] Now, where to go withwages and salaries, savings and inheritances? Luxury goods like Patek-Philippe orRolex watches seem to have promises. Yachts and vintage cars are to cause pretty
high storage costs. Also, not every young artist is to become famous in the long run.
What I could recommend without restrictions are copper and rare earths whereby theformer is again causing high storage costs and the latter really difficult to obtain. As
far as I’m concerned, I like to invest in vinyl disks yet their increase in value seems tobe rather vague, too.
All these thoughts and considerations came to mind while searching Ebay for
Accuphase components. Actually, there aren’t many on offer and if so, I wouldconsider a twenty-year-old Accuphase integrated quite expensive still. Well, theirincrease in value does not appear to be an issue either, even if taking inflation intoaccount. At least they seem to be more stable than the Euro and are not hidden invaults like Fabergé eggs but do offer a palpable benefit: they are enhancing quality oflife. Depending on one’s religious orientation, there are different aspects to this but
the likelihood that we all have got one life only is very high and hence making thebest of it and improving its quality sounds reasonable, doesn’t it? By the way, whilst
all these odd associations are still haunting my mind there is an appealing guarantor
for more groove standing in front of me, namely Accuphase’s power amp P-6100. It
was frustrating to realize that the complementary pre-amplifier C-2820 had to stay inthe magazine’s listening room, at least for the time being.
Nevertheless, P.I.A. [Accuphase’s distributor in Germany] was so kind to
supply the editorial office with a complete chain of Accuphase components. Well, no,they in fact insisted to start right at the wall outlet – of which we’ve got altogether six
sharing three direct lines to the fuse box – in order to have the current wellconditioned by the PS-1220 Clean Power Supply unit. This mighty “multiple socket”
would even show you the degree of current contamination. With up to 3%-4% off the1rule, the line voltage appears pretty grubby, yet after conditioning it came as pure as
fresh linen. This was rewarded by the CD/SACD player DP-700 with an audibly
impressive black background in quiet musical passages. Although the player is notpart of this review, I should still refer to a detail which in little and non-descript is toexpress nearly everything Accuphase stands for: open tray, put in CD, close tray,
read data. All this takes place so silently that you can hear a pin drop.
Eventually, the super-preamp C-2820 arrived whereupon it also found a powersocket at the P-1220. All has been said about the tactile and mechanical/electronic
qualities of Accuphase components, but not from everyone. So, it’s now my turn tomarvel at the Japanese craftsmanship. Let me begin with the volume control which
can be turned as smooth as a genuine high-precision potentiometer. While doing thisit sort of collects a volume position which is simultaneously processed by a CPU.
Conventional potentiometers, which are made to set the volume by means of variable
resistivity, have not been used by Accuphase for quite some time. It’s because they
are said to also change the impedance of the amplification circuitry while turning thevolume, which – in particular at low listening levels – would then degrade the signalto-noise ratio. So what, has anyone out there ever heard a “noisy” Accuphase?
Anyway, the so-called AAVA circuitry was first employed about five years ago
in the C-2000-models of Accuphase’s pre-amplifiers, whereby this circuitry conveys
its mode of operation in the unabridged name: Accuphase Analog Vari-gain
Amplifier. Each music signal coming into the amplifier as voltage is initially converted
to current and then divided into 16 weighted stages. A trick which is to takecomplexity from the circuitry because currents can be more conveniently added, later
converted to voltage again and eventually applied to the balanced and unbalanced
outputs of the amp. However prior to this the aforementioned 16 current stages are
combined in over 65,000 states which is to result in a highly precise and entirely
channel-separated volume level, whereby frequency and tonality of the musicalsignal remain completely untouched during this process. Well, this as far as theory
goes.
A glance beneath the mirror finished wooden case reveals the dual-monoconstruction featuring two toroidal core transformers and four electrolytic capacitorsof each 10,000 µF. The discrete amplification boards are vertically mounted inside acompartment on some kind of shock-absorbers. A total of 16 such modular boards
are arranged separately for left and right channel on a motherboard. They areembracing line input, balanced input, AAVA and other circuit stages as well as theheadphone amplification – the latter likewise in a discrete layout, of course. Asneeded, a sub-panel smoothly opens like flowing honey and gives access to anumber of additional functions: phase inversion for each input, loudness, tapemonitor, to name but a few. The C-2820 can certainly not be accused to offer merely
disproportionate purism. A worthwhile feature with respect to sonic enhancement
seems to be the possibility of having the preamp’s overall gain matched to the power
amplifier.
Although the AAVA circuitry is said to have absolutely no sonic “finger print” I
still had the impression that the C-2820 excels in rendering dynamic passages in therange between position 9 and 1 o’clock of the volume knob. I could enjoy this when
listening to vinyl through the optional phono module AD-2820. In particular somevintage recordings can clearly display the meaning of musical dynamics. With the2Brinkmann “Oasis” turntable as source, the “Perla Musica” played a bit softer but also
more restrained. However from an objective point of view neither of them wassuperior to the other which would rather speak for a synergetic effect than against
this outstanding phono equalizer-amplifier with tubes from bFly (see review on page28). That’s just the way it is: each circuitry has got its ideal respectively optimal areaof operation and in cooperation with the four-stage gain switch of the P-6100, theC-2820 makes even the most minor changes audibly perceivable.
The P-6100 has been designed as the stereo variant of Accuphase’smonophonic power amps M-6000. It incorporates the same instrumentation amplifier
technologies, a form of differential amplifier, which, as opposed to rather ordinary
operational amplifiers, yields the advantage of better common-mode rejection.
However in order to have a real benefit from this technology in audio applications it ismandatory to resort to specially selected parts and components for the circuitry. TheP-6100 is likewise embracing a discrete circuit topology with partly parallel working
identical circuits and eight power MOS-FETs in parallel push-pull configuration per
channel. A small negative feedback signal is returned to the inputs by means of a
feedback amplifier. This is the reason why the P-6100 is free of distortions at evenvery high frequencies. A switch at the rear panel can transform the amp into amonophonic one or allows for either horizontal or vertical bi-amping.
The sound of Accuphase is bewitching me since I’m leading a hi-fi life. As if it
was yesterday, I remember the incisive experience I had with an active andenthusiastic hi-fi dealer in a small town I used to live in. I was about 15 years old thenand looking for an integrated amp with the wilful intent to get the best sound for myhumble funds. However one could read in my face that the funds would by far not beenough to carry the combination of Accuphase C-270 and P-500 home. Nonetheless,they were demonstrated to me via the huge Quadral “Titan” speakers (so to speak
the flavour of the month in those times) because I was evidently too curious. Well,
this was an afternoon that has firmly occupied my sonic memory until today andwhich made me fully aware of the fact that high-end and the blare from ordinary“stereo gear” have absolutely nothing in common. Then upon a bashful glance at theprice tag the next insight hit me: the world is unfair! Today, I’ve got at least an orangecoloured band with Accuphase lettering gracing my bunch of keys. In the meantime it
has become pretty grubby and frayed and the lettering looks worn.
But when in our listening room I’m going to squeeze Gamut’s silver speaker
cables into the massive binding posts of the P-6100 I still know exactly why I’ve got
hooked on this brand. This power amp is emanating perfection and aplomb in every
detail. Admittedly, one neither can acquire it these days with the salary from a holiday
job. The world’s still an unfair place, isn’t it? In some way I have the sincere hope thatall the efforts on the side of P.I.A. with respect to solid, well-working dealerships,
meticulous product presentation and last but not least a strict sales and service policy
will eventually have a meaning in so far that with such demonstrations of musicality
masses of teenagers worldwide could become dedicated followers forever. I do
wholeheartedly wish this to Accuphase and all young people.

I was lucky enough to audition this amplifier combination in our listening room
for several months at various speaker systems. The amps are to seduce everyone toeavesdrop into oneself in order to get the best out of it. The McIntosh MC601 or3

Gamut’s M250 mono amps had the Gamut M7 more tightly grabbed in a headlock,yet these elegant floor-standing speakers sounded perfect in form and melodious
only after the C-2820 and P-6100 had been hooked up. The former got to theirprofound results as well-grounded as a knock-out, i.e. like a boxer they applied theirweightiness as a striking argument whereas Accuphase seems to follow a completely
different approach and philosophy: the art of yielding or how to transform thestrengths of a combatant into one’s own – Jiu-Jitsu hi-fi, so to speak. The two musicmachines did not intrude into the liveliness displayed by Ikon Akustik’s “Avance Evo”
speakers but with gentle hands would rather teach their horn tweeters some goodmanners.
Karolina Strassmayer and her quartet “Klaro!” are actually not performing mymost favoured music but their CD Joining Forces (Lilypad Music) is a wonderfully
audiophile jazz recording. Lustrous clear, pure and perfectly transparent is the soundfrom the internationally renowned saxophone player spreading out in our listening
room. The rhythm section is following her seamlessly and with exact timing. The
arrangements are a bit too conservative and harmonious for my taste; blood, sweat
and tears are missing as well as jealousy and passion. Nevertheless a really goodCD. Jazz for senior teachers, produced by an expert hand.
This well-balanced rendition cannot be bettered by the “Avance Evo” whenplaying in other configurations. Likewise Rega’s “RS-10” (see review on page 114)
which was going to commit a deep symbiosis with the P-6100. Eventually this was
the reason why I took both home to be auditioned with my system in my own
environment. Laid-back, yet on the move at any time, the P-6100 could support thelively manner of the English speakers and furthermore add those dabs of colours the“RS-10” was otherwise leaving aside in its hyperactive dynamic rendition. Seductive
Reasoning by the sisters Maggie & Terre Roche (Speakers Corner/Columbia, LP,
KC 33232), recorded under the aegis of Paul Simon at Muscle Shoal Studios, issprouting from the “RS-10” like the awakening of spring. Uncertainty and selfawareness in the feminist era of Aquarius are speaking from the lyric words of thetwo young ladies whilst their bell-like harmonious singing “hart wie Marmelade”(Extrabreit) [“hard as marmalade”] is hovering above the soulful folk rhythm from thelegendary studio.
In particular when shaping midrange and high frequencies this Class-AB
power amp has absolutely no limits. Further down it plays articulated and flexible
whereby it does not kick the basses but has them coming along and lets them runwith full thrust into the blank – then having them shattered at the membrane in justthe right moment. The balanced interconnection of DP-700, C-2820 and P-6100 is tocreate a dream team which in its harmonious and symbiotic willingness to cooperatewith nearly any speaker system is indeed very hard to beat. Most often, when otheramplifier combinations in the listening room played at the Gamut M7 with excellent
and emphatic performance and thought they may have left the Accuphase-trio behind,the latter has already arrived at the finish. “The gentle and weak conquers the hardand strong”, said Laotse – I call this Jiu-Juitsu hi-fi. Banzai!

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